Thermal storage parameter inversion method, device and storage medium for overflow single well circulation system

Abstract

The present invention provides a method, device and storage medium for inverting heat storage parameters of a single well circulation system, wherein the method comprises: decoupling a preset single well flow model and a single well heat transfer model to obtain a fully analytical model of temperature distribution of the single well and a fully analytical model of water head distribution of the single well; obtaining the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the single well to be designed for reservoir; based on the fully analytical model of temperature distribution of the single well, the fully analytical model of water head distribution of the single well, and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, inverting heat storage parameters according to a preset optimization algorithm to design the reservoir of the single well to be designed for the single well. The present invention can solve the technical problem of how to efficiently, comprehensively and accurately obtain the heat storage parameters of the single well circulation in the prior art.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of geothermal development technology, and in particular to a method, device and storage medium for inversion of thermal storage parameters of a single-well circulation system with overflow. Background Art

[0002] The recharging layer and the pumping layer of the overflow single well circulation system are located in the same reservoir. When the pumping and injection pressure difference acts simultaneously and the flow is intense, the permeability coefficient within the pumping and injection radius centered on the borehole will change. Since the overflow single well reservoir is affected by the pumping and injection pressure and temperature at the same time, the heat storage parameters change significantly, which will affect the pumping and injection parameter design and reservoir design transformation of the overflow single well. Commonly used geothermal parameter inversion methods, such as geophysical exploration and geothermal logging exploration methods, cannot obtain comprehensive heat storage parameters of the overflow circulation system, and the obtained heat storage parameters are suitable for the static state of the exploration stage, but not for the dynamic change state of the development stage. Therefore, how to efficiently, comprehensively and accurately obtain the heat storage parameters of the overflow single well circulation has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The present application provides a method, device and storage medium for inverting heat storage parameters of a single-well overflow circulation system to solve the technical problem of how to efficiently, comprehensively and accurately obtain the heat storage parameters of a single-well overflow circulation in the prior art.

[0004] The first aspect of the present invention provides a method for inverting thermal reservoir parameters of a single-well overflow circulation system, comprising: decoupling a preset single-well overflow flow model from the single-well overflow heat transfer model to obtain a fully analytical model of the single-well overflow temperature distribution and a fully analytical model of the single-well overflow water head distribution, wherein the boundary conditions of the parameters in the single-well overflow flow model and the single-well overflow heat transfer model are determined according to the physical parameters of the structural layer in the single-well overflow reservoir to be designed, the single-well overflow flow model and the single-well overflow heat transfer model contain thermal conductivity, permeability and specific heat capacity parameters, the single-well overflow temperature distribution fully analytical model contains thermal conductivity, and the single-well overflow water head distribution fully analytical model contains permeability. The method comprises the following steps: obtaining the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflowing single well for reservoir design; inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm based on the complete analytical model of the temperature distribution of the overflowing single well, the complete analytical model of the water head distribution of the overflowing single well and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, until obtaining the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions; and the thermal storage parameters of the overflowing single well circulation system composed of the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflowing single well for reservoir design.

[0005] The method for inverting the heat storage parameters of a single-well overflow circulation system provided in an embodiment of the present invention decouples the flow model of the single-well overflow from the heat transfer model of the single-well overflow, thereby obtaining, on the one hand, a completely analytical model of the temperature distribution of the single-well overflow and a completely analytical model of the water head distribution of the single-well overflow. Compared with numerical simulation methods or semi-analytical models, this scheme provides a quantitative mathematical relationship, introduces a method for calculating the overflow flow rate, and obtains an analytical function of the water head distribution of a single-well overflow in a medium-deep layer during simultaneous pumping and injection, which can clearly and objectively reflect physical laws and improve the calculation speed and accuracy of the inversion of the heat storage parameters of the single-well overflow circulation system. On the other hand, the heat storage parameters of the single-well overflow circulation system are inverted according to a preset optimization algorithm, and the heat storage parameters of the single-well overflow circulation system are used to design the single-well overflow reservoir and pumping and injection parameters, thereby improving the reliability of the single-well overflow reservoir in the single-well overflow circulation system and the rationality of the heat extraction system.

[0006] Optionally, after the step of inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, the step further includes: inputting the thermal storage parameters of the overflowing single well circulation system into the corresponding fully analytical model of the overflowing single well temperature distribution and the fully analytical model of the overflowing single well water head distribution, and calculating the calculated value of the outlet water temperature and the calculated value of the water level difference at a preset position of the overflowing single well circulation system; comparing the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position and the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameters of the overflowing single well circulation system obtained by the inversion meets the preset requirements.

[0007] Optionally, after the step of verifying whether the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements, it also includes: if it does not meet the preset requirements, adjusting the preset conditions until the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0008] Optionally, after the step of inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, the step further includes: performing random processing on the heat storage parameters of the overflow single well circulation system to obtain a first heat storage parameter; inputting the first heat storage parameter into the corresponding complete analytical model of the overflow single well temperature distribution and the complete analytical model of the overflow single well water head distribution to calculate the calculated value of the outlet water temperature and the calculated value of the water level difference of the overflow single well circulation system at a preset position; comparing the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position and the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, respectively, to verify whether the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0009] Optionally, after the step of verifying whether the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements, it also includes: if it does not meet the preset requirements, re-randomizing the heat storage parameters of the overflow single well circulation system until the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0010] Optionally, the complete analytical model of the temperature distribution of the overflow single well is:

[0011]

[0012]

[0013]

[0014]

[0015]

[0016] Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s(τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i represents the thermal conductivity of the inner well pipe;

[0017] The complete analytical model of the overflow single well head distribution is:

[0018]

[0019] Among them, s i represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are coefficients, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, y represents the direction along the water head radius, The independent variables of Theis well function are the pumping layer and the recharging layer.

[0020] The second aspect of the present invention provides a device for inverting thermal storage parameters of a single-well overflow circulation system, comprising: a first decoupling module, used to decouple a preset single-well overflow flow model from the single-well overflow heat transfer model, and obtain a complete analytical model of the single-well overflow temperature distribution and a complete analytical model of the single-well overflow water head distribution, wherein the boundary conditions of the parameters in the single-well overflow flow model and the single-well overflow heat transfer model are determined according to the physical parameters of the structural layer in the single-well overflow reservoir to be designed, the single-well overflow flow model and the single-well overflow heat transfer model contain thermal conductivity, permeability and specific heat capacity parameters, the single-well overflow temperature distribution complete analytical model contains thermal conductivity, the single-well overflow water head distribution complete analytical model contains permeability and specific heat capacity parameters a first acquisition module, used to obtain the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflow single well to be designed for the reservoir; a first inversion module, used to invert the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm based on the complete analytical model of the temperature distribution of the overflow single well, the complete analytical model of the water head distribution of the overflow single well and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, until the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are obtained, and the thermal storage parameters of the overflow single well circulation system composed of the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are used to design the reservoir and pumping parameters of the overflow single well to be designed for the reservoir.

[0021] The functions performed by the various components in the thermal storage parameter inversion device for a single-well circulation system provided by the present invention have been applied in any of the above-mentioned method embodiments of the first aspect, and therefore will not be described in detail here.

[0022] The third aspect of the present invention provides a computer device, including a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; the memory is used to store computer programs; the processor is used to implement the steps of the thermal storage parameter inversion method of the overflow single well circulation system of the first aspect when executing the program stored in the memory.

[0023] The fourth aspect of the present invention provides a computer-readable storage medium, which stores computer instructions for causing a computer to execute the method for inverting thermal storage parameters of a single-well circulation system with overflow as provided in the first aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic flow chart of a method for inverting thermal storage parameters of a single-well circulation system with overflow provided by an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the structure of a single-well circulation system for overflow provided by an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of the structure of a single-well circulation system for overflow provided by an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of experimental results of a method for inverting thermal storage parameters of a single-well circulation system with overflow provided by an embodiment of the present invention;

[0029] Figure 5 A schematic diagram of experimental results of a method for inverting thermal storage parameters of a single-well circulation system with overflow provided by an embodiment of the present invention;

[0030] Figure 6 A schematic diagram of the structure of a thermal storage parameter inversion device for a single-well circulation system with overflow provided by an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of the structure of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0033] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. Similar words such as "one", "one" or "the" used in the present disclosure do not indicate a quantitative limitation, but rather indicate the presence of at least one. Similar words such as "include" or "comprise" mean that the element or object appearing before the word covers the element or object listed after the word and its equivalent, without excluding other elements or objects.

[0034] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] In view of the technical problems mentioned in the background technology, the embodiment of the present invention provides a method for inverting thermal storage parameters of a single-well circulation system with overflow, such as Figure 1 As shown, the steps of the method include:

[0036] Step S110, decoupling the preset overflow single well flow model and the overflow single well heat transfer model to obtain a fully analytical model of the overflow single well temperature distribution and a fully analytical model of the overflow single well water head distribution, wherein the overflow single well flow model and the overflow single well heat transfer model are constructed according to the physical parameters of each structural layer in the overflow single well to be designed for the reservoir, the overflow single well flow model and the overflow single well heat transfer model include thermal conductivity, permeability and specific heat capacity parameters, the overflow single well temperature distribution fully analytical model includes thermal conductivity, and the overflow single well water head distribution fully analytical model includes permeability and specific heat capacity parameters.

[0037] For example, the schematic diagram of the cross-flow single well circulation system is as follows: Figure 2 , Figure 3 The overflow single well circulation system includes rock and soil layer 1, recharging layer 2, aquifer 3, pumping layer 4, well pipe outer wall 5, inner well pipe 6, and packer 7; interface S1 between upper rock and soil layer and wellhead, interface S2 between recharging layer and rock and soil layer, interface S3 between recharging layer and weak permeable layer, interface S4 between weak permeable layer and pumping layer, interface S5 between weak permeable layer and lower rock and soil layer, ground surface S6 of lower rock and soil layer, lateral boundary S7 of upper rock and soil layer, lateral boundary S8 of recharging layer, lateral boundary S9 of weak permeable layer, lateral boundary S10 of recharging layer, lateral boundary S11 of lower rock and soil layer, interface S12 between outer well pipe and upper rock and soil layer, interface S13 between outer wall of well pipe and recharging layer, and inner well pipe S15 located at upper rock and soil layer S14 and recharging layer.

[0038] In the embodiment of the present application, the overflow single well flow model may be a overflow confined aquifer groundwater seepage model, as shown in formula (1):

[0039]

[0040] Where D a , D p are the thickness of the aquitard and pumping layer, m; K r , K a The permeability coefficients of the recharge layer and the weak permeable layer, m / s; Q p is the pumping volume, m 3 / h; μ is dynamic viscosity, Pa·s; r is head radius, m; s is head, m; τ is time, s.

[0041] The boundary conditions of the parameters in the overflow well flow model can be determined according to the physical parameters of the structural layer of the overflow well to be designed for the reservoir, wherein the physical parameters of the structural layer may include the thickness of the weak permeable layer, the thickness of the pumping layer, the permeability coefficient of the recharge layer, the permeability coefficient of the weak permeable layer, etc. The specific determination method can be based on the head change law conforming to the funnel or inverted funnel law, as shown in formulas (2)-(4):

[0042]

[0043] r→∞,s=0 (3)

[0044] τ=0,s=0 (4)

[0046] The unsteady flow head distribution function s of the pumping layer and the recharging layer with overflow recharge is derived. r (r,τ) and s p (r,τ):

[0047]

[0048]

[0049] Where B is the resistance coefficient, a p represents the pressure conductivity of the pumping layer, a r represents the pressure conductivity of the reinjection layer, Γ p , Γ r is the hydraulic conductivity of the pumping layer and the recharging layer; r b is the borehole radius, m; Q represents flow rate, D represents thickness, subscript r represents recharge layer, and p represents pumping layer.

[0050] As the recharge progresses, when the flow from the recharge layer to the weak permeable layer breaks through the thickness of the weak permeable layer and enters the pumping layer, overflow occurs. The time taken for this process is called the flow breakthrough time τ. B Before flow breakthrough occurs, the pumping flow is replenished by the far end of the pumping layer. After flow breakthrough occurs, the flow of the pumping layer is composed of the overflow flow and the far end of the pumping layer replenishment:

[0051] Q p =Q s +Q l (7)

[0052] Where Q s , Q l are the remote recharge flow and the overflow flow, respectively. 3 / h.

[0053] The size of the overflow flow plays a key role in the pumping temperature. The larger the overflow flow, the more cold fluid enters the pumping layer. The overflow flow is an important parameter for flow heat transfer in the overflow aquifer.

[0054] The permeability is k r The recharge layer with a permeability of k a The weak permeable layer satisfies the law of refraction at any point on the interface:

[0055]

[0056] Among them, α is the incident angle from the recharge layer to the weak permeable layer, and β is the refraction angle.

[0057] Similarly, the seepage refraction relationship between the aquitard and the pumping layer can be obtained:

[0058]

[0059] Among them, β is the incident angle from the weak permeable layer to the pumping layer, and λ is the refraction angle.

[0060] Define the interface between the aquitard and the pumping layer as the reference plane. When overflow occurs, the distance between the cold fluid front that seeps into the pumping layer and the reference plane is Z. p , when τ>τ B , Z p >0, from the geometric relationship:

[0061]

[0062] tanβ=(R thr -R tha )D a (11)

[0063] Where V pH and V pV is the pumping layer and vertical velocity component m / s, R thr and R tha are the thermal influence radii of the recharge layer and the weak permeable layer, m.

[0064] From equations (8)-(11), the cross-flow heat influence radius can be obtained:

[0065]

[0066] The heat influence radius of the recharge layer is:

[0067]

[0068] Where Q inj is the recharging flow rate, m 3 / h; τ is the recharging time, h; ρ sr represents density, C pr represents the specific heat capacity parameter, and the subscript w represents water.

[0069] At the same time, the over-flow rate can be obtained:

[0070]

[0071] Q l (τ) Substitute s r (r,τ) and s p (r,τ), we can obtain the complete analytical solution of the water head distribution function of a single well with overflow and simultaneous pumping and injection, is the porosity, ρ sa , w are respectively the density of aquitard sandstone and the density of water, kg / m 3 ; C pa , C pw are the specific heat capacity parameters of aquitard sandstone and water, J / kg·K, respectively.

[0072] The overflow single well heat transfer model in the embodiment of the present application may include an aquifer heat transfer model, a soil heat transfer model, and a wellbore heat transfer model. Specifically:

[0073] The aquifer heat transfer model is shown in formula (15):

[0074]

[0075] The technical solution of this embodiment can divide time into several steps, and each time step is approximately a quasi-steady-state heat transfer process. The boundary conditions of the heat transfer model in the aquifer are specifically shown in formulas (16)-(17). The specific determination method can be that the temperature value at the wellbore changes with time, and the temperature at the influence radius is the undisturbed temperature of the rock formation.

[0076] r=r b ,T=T r (τ) (16)

[0077] r=r r,th (τ),T=T r,ini (17)

[0078] Among them, T r(τ) is the average temperature of the recharge water at the recharge layer screen at each moment, °C; r r,th (τ) is the heat affected radius of the recharge layer, m; T r,ini v is the initial temperature of the undisturbed state outside the heat influence radius of the reinjection layer; r is the seepage velocity of the recharge layer, m / s.

[0079] By solving the problem, we can get the aquifer in [r b ,r r,th The temperature distribution function within the range of [τ] is:

[0080]

[0081] in, λ m is the thermal conductivity, heat affected radius r r,th and the recharging water temperature T r is a function of time, so the temperature of the reinjection layer is T rth is a function of radius and time.

[0082] From (18), we can further b ,r r,th (τ)] within the range T rth The average temperature of the overflow temperature T tha , and then by Q s (τ), Q l (τ) and the weighted calculation of the heat capacity of the sandstone in the pumping layer can obtain the temperature distribution of the pumping layer as follows:

[0083]

[0084] Among them, C pp , C pa are the volume specific heat capacity parameters of the pumping layer fluid, [r b ,r r,th (τ)] range.

[0085] The soil heat transfer model is shown in formula (20):

[0086] The wellbore is very small relative to the soil. The heat transfer between the wellbore and the soil can be treated as a linear heat source with homogeneity in the horizontal direction. The soil heat transfer model is shown in formula (20):

[0087]

[0088] λ x , z are the thermal conductivity in the X, Y and Z directions, W / (m·K); ρ s is soil density, kg / m 3 ;cs is the soil specific heat capacity parameter, J / (kg·℃).

[0089] There is no heat exchange around the heat influence radius. The upper surface is the surface convection boundary, and the lower surface is the earth heat flow boundary. l , W / m 2 The boundary conditions are as shown in formulas (21)-(25). The specific determination method can be that the temperature of the temperature field at the initial moment is the same as the initial temperature, the temperature change rate at the impact radius in the horizontal direction is 0, and the temperature change rate at the wellhead in the vertical direction meets the second type of heat exchange boundary, and meets the third type of heat exchange boundary at the bottom of the well.

[0090] θ(x,y,z,τ)| τ＝0 =0 (21)

[0091]

[0092]

[0093]

[0094]

[0095] θ is the excess temperature, θ(x,y,z,τ)=T(x,y,z,τ)-T0, is the change of soil temperature field relative to the initial temperature T0, h1 and h2 are the convective heat transfer coefficients of the upper and lower surfaces of the soil, respectively.

[0096] Therefore, the well wall temperature is the temperature along the well wall direction, that is, the temperature when x=0, y=0, T w (0,0,z,τ)=T0(0,0,z,0)+θ(0,0,z,τ).

[0097] Where T0(0,0,z,0) is the temperature along the wellbore wall at the initial moment. From the known conditions, we can know that the wellbore wall temperature can be obtained by knowing θ(0,0,z,τ). θ(0,0,z,τ) can be obtained from the control equations, initial conditions and boundary conditions of formulas (20)-(25).

[0098] The wellbore heat transfer model is constructed as shown in formula (26) and formula (27):

[0099] Establish the energy balance equation for the inner tube:

[0100]

[0101] The energy balance equation for the annular space is established:

[0102]

[0103] cf is the volume specific heat capacity parameter of the fluid, kJ / (m 3 k); Q m is the pumping flow rate, kg / s; T f,up is the temperature of the fluid in the inner tube, °C; T f,down is the temperature of the fluid in the annular space, °C; z is the depth from the wellhead, m; T w is the well wall temperature, ℃; R1 is the total thermal resistance between the inner and outer tubes, (m·k) / W; R2 is the total thermal resistance between the outer tube and the well wall, (m·k) / W.

[0104]

[0105]

[0106] r 1o 、r 1i are the outer radius of the inner tube and the inner radius of the inner tube, respectively, m; λ1 is the thermal conductivity of the inner tube, W / (m·k); h1 and h2 are the convective heat transfer coefficients of the fluid in the inner tube and the outer tube, respectively, W / (m 2 ·k); R a , R c and R s They are the convection thermal resistance of pipeline flow, the conduction thermal resistance through the well pipe and the well wall, and the conduction thermal resistance of the rock formation, (m·k) / W.

[0107] The initial temperature distribution of the wellbore wall is linearly related to the geothermal gradient:

[0108] T w (z) = T sur +a·z (30)

[0109] T sur is the surface temperature, ℃; a is the geothermal gradient, ℃ / km.

[0110] The boundary conditions include the inlet boundary conditions and the bottom hole boundary conditions, which are shown in formula (31) and formula (32) respectively:

[0111] The specific method of determining the inlet boundary condition is that the well wall temperature is the annular space temperature, and the inlet temperature is the reinjection temperature.

[0112] T w (z) = T f,down (z) = T inj (31)

[0113] The bottom hole boundary condition can be specifically determined in such a way that the temperature of the annular space at the bottom hole is the same as the temperature of the inner tube fluid.

[0114] T f,down (z) = T f,up (z) (32)

[0115] Substituting equations (28)-(32) into equations (26) and (27), we can obtain the fluid temperature distribution function of the inner and outer pipes of the wellbore:

[0116]

[0117]

[0118]

[0119]

[0120] γ=T inj -T sur +ac f Q m R2 (37)

[0121] This embodiment uses the wellhead position as a reference to construct a fully analytical model for the temperature distribution of a single well with overflow. Therefore, the pumping temperature at the wellhead is the fully analytical solution for the temperature distribution of a single well with overflow that needs to be calculated in the end, that is, the temperature of the riser when z=0 (wellhead position):

[0122]

[0123] From (35)-(37), we know that α, β, and γ. From (29), we know that R2 is a function of time. Therefore, the temperature distribution of a single well in the overflow is completely analyzed by the model T. f,p (τ) is also a function of time, that is, the complete analytical model of temperature distribution in a single well is:

[0124]

[0125] Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s (τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i Indicates the thermal conductivity of the inner well tube

[0126] It should be noted that those skilled in the art can also use other positions as references to construct a complete analytical model of temperature distribution in a single well, and this is not limited here.

[0127] The permeability coefficient of the pumping layer and the sandstone of the permeable layer conforms to the exponential decay law, which is:

[0128] k=ae -bτ (40)

[0129] Where a and b are the coefficients of the attenuation function, and τ is the flow time.

[0130] Based on the decoupling of the above models (5), (6), and (39), the fully analytical model of the hydraulic head distribution of a single well with overflow is:

[0131]

[0132] Among them, s i represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are coefficients, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, and y represents the direction along the water head radius. The independent variables of Theis well function are the pumping layer and the recharging layer.

[0133] Step S120, obtaining the measured value of the outlet water temperature and the measured value of the water level difference at a preset position of the overflow single well circulation system.

[0134] Exemplarily, the preset position may be the wellhead position of the overflow single-well circulation system, which can be determined by those skilled in the art based on actual conditions and is not limited here.

[0135] Step S130, based on the fully analytical model of the temperature distribution of the overflowing single well, the fully analytical model of the head distribution of the overflowing single well, and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, invert the thermal conductivity, the permeability and the specific heat capacity parameters according to the preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained. The thermal storage parameters of the overflowing single well circulation system composed of the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflowing single well for which the reservoir design is to be performed.

[0136] Exemplarily, the preset optimization algorithm can be an optimization algorithm, such as a genetic algorithm, or other optimization algorithms known to those skilled in the art, which are not limited here. According to the preset optimization algorithm, the thermal conductivity, permeability and specific heat capacity parameters are inverted. The specific inversion implementation process includes initializing the boundary conditions, initial conditions and parameters to be estimated of the actual problems involved in the obtained complete analytical model of the temperature distribution of a single well with overflow and the complete analytical model of the head distribution of a single well with overflow, and continuously adjusting the parameters to be estimated in the model through the optimization algorithm, and the model outputs different calculation results. The calculated results of the model are compared with the measured values ​​until the objective function and the limiting conditions set in the optimization algorithm are met, and the inversion values ​​of the parameters to be estimated in the model can be obtained. Taking the preset optimization algorithm as a genetic algorithm as an example, a nonlinear optimization model is constructed based on the complete analytical model of the temperature distribution of a single well with overflow and the complete analytical model of the head distribution of a single well with overflow, and the coefficients and parameters of the nonlinear optimization model are calculated using a genetic algorithm, so as to obtain the inverted parameters.

[0137] Specifically, the complete analytical model of temperature distribution of a single well with overflow includes the thermal conductivity λ of the aquifer and the weak permeable layer, and the complete analytical model of water head distribution of a single well with overflow includes the permeability coefficient K of the pumping layer, the specific heat capacity parameter C of the aquifer and the weak permeable layer p The nonlinear optimization model is constructed based on the analytical function, as shown in formulas (42)-(43):

[0138]

[0139]

[0140]

[0141] θ min ≤{λ r ,λ a}≤θ max (42)

[0142]

[0143]

[0144]

[0145] θ min ≤{a,b,K a ,K p ,C pa ,C pp}≤θ max (43)

[0146] Among them, λ r represents the thermal conductivity of the recharge layer, λ a represents the thermal conductivity of the reinjection layer, T f,p Indicates the calculated value of the outlet water temperature, C pp , C pa are the volume specific heat capacity parameters of the pumping layer fluid, [r b ,r r,th (τ)], T * f,p Indicates the measured value of the outlet water temperature, s i Indicates the calculated value of water level difference, value, s * i It represents the measured value of water level difference, ε1 and ε2 are error constraints, such as 0.001~0.005, which can be set according to the actual situation and are not restricted here.

[0147] The preset conditions may include, but are not limited to, error constraint conditions and variance minimum constraint conditions, and those skilled in the art may set them according to actual needs, which are not limited here.

[0148] The objective functions are to minimize the variance of the measured and analytically calculated water outlet temperature and the variance of the measured and analytically calculated water level difference, respectively. The constraints are that the measured and calculated values ​​meet the specified absolute error and percentage error. The improved genetic algorithm is used for global optimization. When the convergence condition is not met, the initial value of the genetic algorithm is readjusted until the convergence condition is met.

[0149] The thermal conductivity λ of the aquifer and aquitard is inverted by the nonlinear optimization model. First, the boundary conditions, initial conditions and parameters to be estimated of the actual problem are input into the complete analytical model of temperature distribution of a single well with overflow and the complete analytical model of water head distribution of a single well with overflow. The calculated pumping temperature function contains the parameter to be estimated λ, which constitutes a nonlinear optimization model with the measured pumping temperature. The corresponding constraints are set, and the optimal solution is found through the improved genetic algorithm to obtain the thermal conductivity λ of the aquifer and aquitard. Similarly, the permeability coefficient K of the pumping layer, the specific heat capacity parameter C of the aquifer and aquitard p , which is also obtained through the above steps. After obtaining the permeability coefficient K of the pumping layer, according to the permeability law k = ae -bτThe coefficients a and b can be obtained, brought back into the fully analytical model and then compared with the measured results. The final inversion results are obtained when the preset conditions are met. The thermal reservoir parameters of the overflow single well circulation system composed of the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflow single well to be designed, which can directly or indirectly guide the design of the pumping flow rate, the site selection and transformation of the thermal reservoir.

[0150] This embodiment provides a boundary condition setting method, specifically:

[0151] (1) The inlet of the outer tube annular space is a constant flow and constant temperature boundary;

[0152] Q(r,z)=Q inj , T(r,z)=T inj (44)

[0153] Among them, Q(r,z) represents the flow function, Q inj is the pumping flow rate, m 3 / h; T(r,z) represents the temperature function, T inj is the recharging temperature, ℃.

[0154] (2) The inner tube outlet is a constant flow rate and temperature outflow boundary;

[0155]

[0156] Where n represents the normal vector, λ eq represents the equivalent thermal conductivity of the inner tube, Represents the temperature gradient of the inner tube.

[0157] (3) The upper and lower boundaries of the aquiclude and the distal side boundary are flow-free and constant temperature boundaries;

[0158] -n·(ρ w u)|s 1，2，5，6，7，11 =0,T(r,z)|s 1,6,7,11 =T0+a·z (46)

[0159] Where n represents the normal vector, ρ w represents the density of water, u represents the fluid velocity, T0 is the surface temperature, such as 15℃; a is the geothermal gradient, ℃ / m; z is the well depth, m.

[0160] (4) The far side boundary of the pumped aquifer and aquitard is a constant temperature and constant water head boundary;

[0161] H(r,z)|s 8，9，10 =H0,T(r,z)|s 10 =T0+a·z (47)

[0162] Among them, H(r,z) represents the water head at interfaces 8, 9, and 10, and H0 represents the water head constant.

[0163] (5) The interface between the aquifer and the impermeable layer, the pumping layer and the weak permeable layer, the interface between the outer pipe and the recharging layer, and the interface between the inner pipe and the pumping layer are continuous boundaries;

[0164] -n1·(ρ w u)1=n2·(ρ w u)2, at interfaces S2, S3, S4, S5, S13, S16 (48)

[0165]

[0166] Among them, n1 and n2 represent the normal vectors of the two equations.

[0167] (6) The interface between the outer tube and the water barrier adopts a no-flow, temperature outflow boundary;

[0168]

[0169] Those skilled in the art may set the boundary conditions according to actual needs, and no limitation is made here.

[0170] This embodiment provides a set of initial conditions, specifically, as shown in Table 1:

[0171] Table 1 Initial conditions

[0172]

[0173] Those skilled in the art may set the initial conditions according to actual needs, and no limitation is made here.

[0174] The method for inverting the heat storage parameters of a single-well overflow circulation system provided in an embodiment of the present invention decouples the flow model of the single-well overflow from the heat transfer model of the single-well overflow, thereby obtaining, on the one hand, a completely analytical model of the temperature distribution of the single-well overflow and a completely analytical model of the water head distribution of the single-well overflow. Compared with numerical simulation methods or semi-analytical models, this scheme provides a quantitative mathematical relationship, introduces a method for calculating the overflow flow rate, and obtains an analytical function of the water head distribution of a single-well overflow in a medium-deep layer during simultaneous pumping and injection, which can clearly and objectively reflect physical laws and improve the calculation speed and accuracy of the inversion of the heat storage parameters of the single-well overflow circulation system. On the other hand, the heat storage parameters of the single-well overflow circulation system are inverted according to a preset optimization algorithm, and the heat storage parameters of the single-well overflow circulation system are used to design the single-well overflow reservoir and pumping and injection parameters, thereby improving the reliability of the single-well overflow reservoir in the single-well overflow circulation system and the rationality of the heat extraction system.

[0175] As an optional embodiment of the present invention, it also includes:

[0176] Step S210, input the thermal storage parameters of the overflow single well circulation system into the corresponding overflow single well temperature distribution complete analytical model and the overflow single well head distribution complete analytical model, and calculate the outlet water temperature calculated value and the water level difference calculated value at the preset position of the overflow single well circulation system.

[0177] Exemplarily, the heat storage parameters obtained by inversion are brought into the fully analytical model, and the calculated value of the outlet water temperature and the calculated value of the water level difference at the preset position of the overflow single well circulation system are calculated by the forward method. The preset position in the calculated value of the outlet water temperature and the calculated value of the water level difference at the preset position of the overflow single well circulation system is calculated to correspond to or be the same as the preset position in the obtained measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflow single well circulation system.

[0178] Step S220, compare the calculated value of the outlet water temperature at the preset position with the actual value of the outlet water temperature at the preset position, and compare the calculated value of the water level difference at the preset position with the actual value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0179] For example, the preset requirements can be set by those skilled in the art according to actual conditions, and will not be set here. Specifically, by comparing the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position and the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, it is verified whether the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements. If the error is less than a preset threshold, such as 5%, it can be determined that the heat storage parameters obtained by the inversion meet the preset requirements.

[0180] The method for inverting thermal storage parameters of a single-well overflow circulation system provided in an embodiment of the present invention brings the thermal storage parameters obtained by inversion into a complete analytical model through a forward modeling method, calculates the calculated value of the outlet water temperature and the calculated value of the water level difference at a preset position of the single-well overflow circulation system, and compares the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position, as well as the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, to determine whether the accuracy of the thermal storage parameters obtained by inversion meets the preset requirements, thereby obtaining accurate and reliable thermal storage parameters for designing the reservoir of the single-well overflow for which reservoir design is to be performed, thereby improving the quality reliability of the single-well overflow circulation system.

[0181] As an optional embodiment of the present invention, it also includes:

[0182] Step S310: If the preset requirements are not met, the preset conditions are adjusted until the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0183] Exemplarily, if the heat storage parameters obtained by inversion do not meet the preset requirements, such as insufficient accuracy, the preset conditions are adjusted, such as adjusting the constraint range of the error constraint conditions, and the heat storage parameters are re-inverted using an optimization algorithm until the accuracy of the heat storage parameters of the overflow single-well circulation system obtained by the inversion meets the preset requirements.

[0184] The method for inverting heat storage parameters of a single-well circulation system with overflow provided by the embodiment of the present invention can, by adjusting preset conditions, obtain heat storage parameters of a single-well circulation system with overflow with accuracy that meets preset requirements; on the other hand, it can determine appropriate preset conditions.

[0185] As an optional embodiment of the present invention, it also includes:

[0186] Step S410, randomizing the heat storage parameters of the overflow single well circulation system to obtain first heat storage parameters.

[0187] For example, the randomization process may include but is not limited to Gaussian randomization, which can be determined by those skilled in the art according to actual needs and is not limited here. In this embodiment, Gaussian randomization is used as an example to perform Gaussian randomization on the thermal reservoir parameters of the overflow single well circulation system, so as to obtain thermal reservoir parameters that are more homogeneous and close to the actual reservoir characteristics.

[0188] Step S420, inputting the first heat storage parameter into the corresponding fully analytical model of the overflow single well temperature distribution and the fully analytical model of the overflow single well water head distribution, and calculating the calculated value of the outlet water temperature and the calculated value of the water level difference of the overflow single well circulation system at a preset position.

[0189] Step S430, respectively compare the calculated value of the outlet water temperature at the preset position with the actual value of the outlet water temperature at the preset position, and the calculated value of the water level difference at the preset position with the actual value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

[0190] In this embodiment, step S420 to step S430 are similar to the description of the corresponding parts above and will not be repeated here.

[0191] The method for inverting thermal storage parameters of a single-well overflow circulation system provided in an embodiment of the present invention performs random processing on the thermal storage parameters of the single-well overflow circulation system to obtain thermal storage parameters that are more homogeneous and close to actual reservoir characteristics.

[0192] As an optional embodiment of the present invention, it also includes:

[0193] Step S510: if the preset requirements are not met, randomizing the heat storage parameters of the overflowing single well circulation system again until the accuracy of the heat storage parameters of the overflowing single well circulation system obtained by the inversion meets the preset requirements.

[0194] For example, if the heat storage parameters obtained by random processing do not meet the preset requirements, such as insufficient accuracy, the heat storage parameters of the overflowing single well circulation system are randomized again or other optional random processing methods are used to obtain heat storage parameters that are more homogeneous and close to the actual reservoir characteristics, until the accuracy of the heat storage parameters of the overflowing single well circulation system obtained by inversion meets the preset requirements.

[0195] The method for inverting the thermal storage parameters of a single-well overflow circulation system provided in an embodiment of the present invention obtains thermal storage parameters that are more homogeneous and closer to actual reservoir characteristics by re-randomizing the thermal storage parameters of the single-well overflow circulation system, thereby ensuring the reliability of the reservoir design reference data of the single-well overflow to be used for reservoir design.

[0196] As an optional embodiment of the present invention, the complete analytical model of the temperature distribution of the overflow single well is:

[0197]

[0198]

[0199]

[0200]

[0201]

[0202] Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s (τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i represents the thermal conductivity of the inner well pipe;

[0203] The complete analytical model of the overflow single well head distribution is:

[0204]

[0205] Among them, s ii represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are coefficients, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, y represents the direction along the water head radius, The independent variables of Theis well function are the pumping layer and the recharging layer.

[0206] In order to verify the performance of the thermal reservoir parameter inversion method for the overflow single well circulation system provided in the above embodiment, the following experiments and experimental results are provided in the embodiment of the present invention:

[0207] Five different working conditions are selected, as shown in Table 2:

[0208] Table 2 Experimental conditions

[0209]

[0210] The inversion results are shown in Table 3:

[0211] Table 3 Inversion results

[0212]

[0213]

[0214] Calculated and measured values ​​of water level changes, such as Figure 4 shown.

[0215] The calculated and measured values ​​of the pumping water temperature are as follows: Figure 5 shown.

[0216] Figure 6 A device for inverting heat storage parameters of a single-well circulation system with overflow is provided in one embodiment of the present invention, comprising:

[0217] The first decoupling module 710 is used to decouple the preset overflow single well flow model and the overflow single well heat transfer model to obtain the overflow single well temperature distribution complete analytical model and the overflow single well water head distribution complete analytical model, wherein the boundary conditions of the parameters in the overflow single well flow model and the overflow single well heat transfer model are determined according to the physical parameters of the structural layer in the overflow single well to be designed for the reservoir, the overflow single well flow model and the overflow single well heat transfer model include thermal conductivity, permeability and specific heat capacity parameters, the overflow single well temperature distribution complete analytical model includes thermal conductivity, and the overflow single well water head distribution complete analytical model includes permeability and specific heat capacity parameters. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0218] The first acquisition module 720 is used to obtain the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflow well to be designed for the reservoir. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0219] The first inversion module 730 is used to invert the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm based on the complete analytical model of the temperature distribution of the overflowing single well, the complete analytical model of the water head distribution of the overflowing single well, and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, until the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are obtained. The thermal storage parameters of the overflowing single well circulation system composed of the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflowing single well to be designed. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0220] As an optional implementation device of the present invention, it also includes:

[0221] The first input module is used to input the thermal storage parameters of the overflow single well circulation system into the corresponding overflow single well temperature distribution complete analytical model and the overflow single well water head distribution complete analytical model, and calculate the outlet water temperature calculation value and the water level difference calculation value at the preset position of the overflow single well circulation system. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0222] The first comparison module is used to compare the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position and the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameter of the overflow single well circulation system obtained by the inversion meets the preset requirements. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0223] As an optional implementation device of the present invention, it also includes:

[0224] The first adjustment module is used to adjust the preset conditions if the preset requirements are not met until the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements. For details, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0225] As an optional implementation device of the present invention, it also includes:

[0226] The first processing module is used to perform random processing on the heat storage parameter of the overflow single well circulation system to obtain the first heat storage parameter. For details, please refer to the description of the corresponding part of the above embodiment, which will not be repeated here.

[0227] The second input module is used to input the first heat storage parameter into the corresponding single well temperature distribution complete analytical model and the single well head distribution complete analytical model, and calculate the outlet water temperature calculation value and the water level difference calculation value of the single well circulation system at the preset position. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0228] The second comparison module is used to compare the calculated value of the outlet water temperature at the preset position with the measured value of the outlet water temperature at the preset position and the calculated value of the water level difference at the preset position with the measured value of the water level difference at the preset position, respectively, to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0229] As an optional implementation device of the present invention, it also includes:

[0230] The second processing module is used to re-randomize the heat storage parameters of the overflow single well circulation system if the preset requirements are not met, until the accuracy of the heat storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements. For details, please refer to the description of the corresponding part in the above embodiment, which will not be repeated here.

[0231] As an optional implementation device of the present invention, it includes: the complete analytical model of the temperature distribution of the overflow single well is:

[0232]

[0233]

[0234]

[0235]

[0236]

[0237] Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s (τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i represents the thermal conductivity of the inner well pipe;

[0238] The complete analytical model of the overflow single well head distribution is:

[0239]

[0240] Among them, s i represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are coefficients, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, y represents the direction along the water head radius, The independent variables of Theis well function are the pumping layer and the recharging layer.

[0241] An embodiment of the present invention provides a computer device, such as Figure 7 As shown, the device includes one or more processors 3010 and a memory 3020, and the memory 3020 includes a persistent memory, a volatile memory, and a hard disk. Figure 7 A processor 3010 is taken as an example. The device may also include: an input device 3030 and an output device 3040.

[0242] The processor 3010, the memory 3020, the input device 3030 and the output device 3040 may be connected via a bus or other means. Figure 7 The example of connecting through bus is taken in the following.

[0243] The processor 3010 may include, but is not limited to, a central processing unit (CPU) and a graphics processing unit (GPU). The processor 3010 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, or a combination of the above chips. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc. The memory 3020 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created according to the use of a thermal storage parameter inversion device for a single well circulation system. In addition, the memory 3020 may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 3020 may optionally include a memory remotely arranged relative to the processor 3010, and these remote memories may be connected to the thermal storage parameter inversion device for the overflow single well circulation system through a network. The input device 3030 may receive a calculation request (or other digital or character information) input by a user, and generate key signal input related to the thermal storage parameter inversion device for the overflow single well circulation system. The output device 3040 may include a display device such as a display screen to output the calculation results.

[0244] The embodiment of the present invention provides a computer-readable storage medium, which stores computer instructions, and the computer storage medium stores computer executable instructions, which can execute the thermal storage parameter inversion method of the overflow single well circulation system in any of the above method embodiments. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory (Flash Memory), a hard disk (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above types of memory.

[0245] The logic and / or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be embodied in any computer-readable storage medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, apparatus, or device and execute instructions), or in conjunction with such instruction execution system, apparatus, or device. For purposes of this specification, "computer-readable storage medium" may be any device that can contain, store, communicate, propagate, or transmit a program for use by an instruction execution system, apparatus, or device, or in conjunction with such instruction execution system, apparatus, or device. More specific examples of computer-readable storage media (a non-exhaustive list) include the following: an electrical connection with one or more wirings (electronic devices), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable storage medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0246] It should be understood that the various parts of the present disclosure can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0247] In the description of this specification, the description with reference to the terms "this embodiment", "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless there is any contradiction. In the description of the present disclosure, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0248] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention.

Claims

1. A method for inverting thermal storage parameters of a single-well circulation system with overflow, characterized in that: include: Decoupling the preset overflow single well flow model and the overflow single well heat transfer model to obtain a complete analytical model of the overflow single well temperature distribution and a complete analytical model of the overflow single well water head distribution, wherein the boundary conditions of the parameters in the overflow single well flow model and the overflow single well heat transfer model are determined according to the physical parameters of the structural layer in the overflow single well for reservoir design, the overflow single well flow model and the overflow single well heat transfer model include thermal conductivity, permeability and specific heat capacity parameters, the overflow single well temperature distribution complete analytical model includes thermal conductivity, and the overflow single well water head distribution complete analytical model includes permeability and specific heat capacity parameters; Obtaining the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflow single well to be designed for the reservoir; Based on the fully analytical model of temperature distribution of the overflowing single well, the fully analytical model of water head distribution of the overflowing single well, and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, the thermal conductivity, the permeability and the specific heat capacity parameters are inverted according to a preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, and the thermal storage parameters of the overflowing single well circulation system composed of the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflowing single well for which the reservoir design is to be performed; The complete analytical model of the temperature distribution of the overflow single well is: Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s (τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i represents the thermal conductivity of the inner well pipe; The complete analytical model of the overflow single well head distribution is: Among them, s i represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are the coefficients of the attenuation function, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, y represents the direction along the water head radius, The independent variables of Theis well function are the pumping layer and the recharging layer.

2. The method for inversion of thermal storage parameters of a single-well circulation system with overflow according to claim 1 is characterized in that: After the step of inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to the preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, the step further includes: Inputting the thermal storage parameters of the overflow single well circulation system into the corresponding overflow single well temperature distribution complete analytical model and the overflow single well water head distribution complete analytical model, and calculating the outlet water temperature calculation value and the water level difference calculation value at the preset position of the overflow single well circulation system; The calculated value of the outlet water temperature at the preset position is compared with the actual value of the outlet water temperature at the preset position, as well as the calculated value of the water level difference at the preset position is compared with the actual value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

3. The method for inversion of thermal storage parameters of a single-well circulation system with overflow according to claim 2 is characterized in that: After the step of verifying whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements, the method further includes: If the preset requirements are not met, the preset conditions are adjusted until the accuracy of the thermal storage parameters of the overflow single-well circulation system obtained by the inversion meets the preset requirements.

4. The method for inversion of thermal storage parameters of a single-well circulation system with overflow according to claim 1, characterized in that: After the step of inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to the preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, the step further includes: Randomizing the heat storage parameter of the overflow single well circulation system to obtain a first heat storage parameter; Inputting the first heat storage parameter into the corresponding single well overflow temperature distribution fully analytical model and the single well overflow head distribution fully analytical model, and calculating the outlet water temperature calculated value and the water level difference calculated value of the single well overflow circulation system at a preset position; The calculated value of the outlet water temperature at the preset position is compared with the actual value of the outlet water temperature at the preset position, and the calculated value of the water level difference at the preset position is compared with the actual value of the water level difference at the preset position to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

5. The method for inversion of thermal storage parameters of a single-well circulation system with overflow according to claim 4 is characterized in that: After the step of verifying whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements, the method further includes: If the preset requirements are not met, the heat storage parameters of the overflowing single-well circulation system are randomized again until the accuracy of the heat storage parameters of the overflowing single-well circulation system obtained by the inversion meets the preset requirements.

6. A device for inverting thermal storage parameters of a single-well circulation system with overflow, characterized in that: include: The first decoupling module is used to decouple the preset overflow single well flow model and the overflow single well heat transfer model to obtain the overflow single well temperature distribution complete analytical model and the overflow single well water head distribution complete analytical model, wherein the boundary conditions of the parameters in the overflow single well flow model and the overflow single well heat transfer model are determined according to the physical parameters of the structural layer in the overflow single well to be designed for the reservoir, the overflow single well flow model and the overflow single well heat transfer model include thermal conductivity, permeability and specific heat capacity parameters, the overflow single well temperature distribution complete analytical model includes thermal conductivity, and the overflow single well water head distribution complete analytical model includes permeability and specific heat capacity parameters; wherein the overflow single well temperature distribution complete analytical model is: Where τ represents time, T f,p (τ) represents the time-varying wellhead pumping temperature, T sur represents the surface temperature, a represents the geothermal gradient, λ represents the thermal conductivity, c f represents the volume specific heat capacity parameter of the fluid, Q m represents the pumping flow rate, R1 represents the total thermal resistance between the inner and outer pipes, R2 represents the total thermal resistance between the outer pipe and the well wall, H represents the overflow single well depth, r 1o 、r 1i represent the outer radius of the inner tube and the inner radius of the inner tube respectively, λ1 represents the thermal conductivity of the inner tube, h1 and h2 represent the convective heat transfer coefficients of the fluid in the inner tube and the outer tube respectively, λ s represents the thermal conductivity of rock formation, a s (τ) represents the thermal diffusion rate of the rock formation that changes with time, r w Represents the outer radius of the wellbore, r 2i represents the thermal conductivity of the inner well pipe; The complete analytical model of the overflow single well head distribution is: Among them, s i represents the head difference of the single well pumping and injection at the same time, τ represents time, Q p (τ) represents the amount of water pumped over time, K p represents the permeability coefficient of the pumping layer, D p represents the thickness of the pumping layer, a p represents the pressure conductivity coefficient of the pumping layer, r represents the head radius, a and b are the coefficients of the attenuation function, and D a Denotes the thickness of the aquitard, D r Represents the thickness of the recharge layer, K a represents the permeability coefficient of the aquitard, Q r (τ) represents the recharge volume changing with time, a r represents the pressure conductivity coefficient of the recharge layer, y represents the direction along the water head radius, The independent variables of the Theis well function are the pumping layer and the recharging layer; The first acquisition module is used to obtain the measured value of the outlet water temperature and the measured value of the water level difference at the preset position of the overflow single well to be designed for the reservoir; The first inversion module is used to invert the thermal conductivity, the permeability and the specific heat capacity parameters according to a preset optimization algorithm based on a complete analytical model of the temperature distribution of the overflowing single well, a complete analytical model of the water head distribution of the overflowing single well, and the measured value of the outlet water temperature and the measured value of the water level difference at the preset position, until the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are obtained. The heat storage parameters of the overflowing single well circulation system composed of the target thermal conductivity, target permeability and target specific heat capacity parameters that meet the preset conditions are used to design the reservoir of the overflowing single well for which reservoir design is to be performed.

7. The device for inverting heat storage parameters of a single-well circulation system according to claim 6, characterized in that: include: After the step of inverting the thermal conductivity, the permeability and the specific heat capacity parameters according to the preset optimization algorithm until the target thermal conductivity, the target permeability and the target specific heat capacity parameters that meet the preset conditions are obtained, the step further includes: The first input module is used to input the thermal storage parameters of the overflow single well circulation system into the corresponding overflow single well temperature distribution complete analytical model and the overflow single well water head distribution complete analytical model, and calculate the outlet water temperature calculation value and the water level difference calculation value at the preset position of the overflow single well circulation system; The first comparison module is used to compare the calculated value of the outlet water temperature at the preset position with the actual value of the outlet water temperature at the preset position, and the calculated value of the water level difference at the preset position with the actual value of the water level difference at the preset position, to verify whether the accuracy of the thermal storage parameters of the overflow single well circulation system obtained by the inversion meets the preset requirements.

8. A computer device, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; Memory, used to store computer programs; The processor is used to implement the steps of the method for inverting thermal storage parameters of a single-well circulation system with overflow as described in any one of claims 1 to 5 when executing the program stored in the memory.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for inverting thermal storage parameters of a single-well circulation system with overflow are implemented as described in any one of claims 1 to 5.

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