Deepwater drilling overflow leakage detection method, device, medium and equipment

Abstract

The invention relates to a deepwater drilling overflow leakage detection method and device, a medium and equipment. The method comprises the steps that a fluid mechanics model of deepwater drilling shaft-stratum-marine riser pressurization pipeline coupling flow is established; inputting related parameters of a shaft and a stratum and basic parameters of a drilling fluid into the model, calculating a flow resistance parameter between a reservoir and the shaft, a circulating pressure consumption parameter of the shaft and an annulus fluid inertia coefficient of the shaft, and establishing a nonlinear state and an observation equation; performing linearization processing on the nonlinear state and the observation equation; discretizing a linear state and an observation equation, constructing a state and observation matrix discrete equation at the current moment, and establishing a Kalman filtering correction prediction model at the current moment; and calculating a linear state and a state and observation coefficient matrix of the observation equation, inputting real-time drilling data and the state and observation coefficient matrix into the Kalman filtering correction prediction model, and finally obtaining a well kick and well leakage prediction result.

Description

Technical Field

[0001] The invention relates to a deepwater drilling overflow detection method, device, medium and equipment, and belongs to the field of overflow and leakage monitoring in wellbore. Background Art

[0002] The overburden pressure of deepwater oil and gas reservoirs is low, resulting in a narrow safe operating window for deepwater drilling pressure and a high risk of drilling overflow. The blowout preventer for conventional deepwater drilling is installed on the seabed and connected to the platform processing equipment through a riser. Since the pressure bearing capacity of the riser is low, in order to avoid a large amount of gas entering the riser and causing the riser to fail and be damaged, deepwater drilling has high requirements for the timeliness of overflow monitoring technology.

[0003] However, the existing deepwater drilling overflow monitoring technology is based on the principle of volume expansion, that is, the formation fluid that invades the annulus expands in volume in the annulus, resulting in a decrease in the density of the mixed fluid in the annulus, forming a pressure difference in the "U"-shaped flow system composed of the drill string and the annulus, causing flow changes. This method easily causes a large amount of formation fluid to enter the watertight pipe, making the platform disposal difficult and the disposal risk high. Therefore, conventional overflow monitoring methods can no longer meet the needs of early monitoring of deepwater drilling overflows.

[0004] How to identify the invading fluid before its volume expands, avoid the formation of solid hydrates after the gas enters the underwater blowout preventer, causing the blowout preventer to fail, and control the volume of gas entering the riser to a minimum, is extremely important for deepwater drilling overflow monitoring. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a deepwater drilling leakage detection method, device, medium and equipment. The method combines the characteristics of conventional deepwater riser drilling technology, adds the formation fluid inflow item of the bottom hole section on the basis of the original U-shaped tube model, and establishes the first "Y" type tube model of the present invention, namely the "large Y cycle"; the booster pump pipeline and the annulus of the riser section and the annulus below the mud line are regarded as the second "Y" type tube model, namely the "small Y cycle". The flow state characterization models of the above two "Y" type tube models are respectively established, and the analysis and prediction of the coupled flow leakage state of the wellbore and the formation are realized by introducing the Kalman filter prediction method.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A deepwater drilling leak detection method, comprising:

[0008] A double "Y" type pipe fluid dynamics model for coupled flow of deepwater drilling wellbore-formation-riser booster pipeline is established;

[0009] Obtain the current drilling data, filter and process it and import it into the double "Y" tube fluid mechanics model to determine the basic information of the reservoir and wellbore under the current drilling status;

[0010] On the basis of the previous geological exploration data and real-time drilling data, the data including the wellbore and formation related parameters and the basic parameters of the drilling fluid are input into the double "Y" type pipe fluid mechanics model at the current moment, and the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient are calculated at the current moment, so as to establish the double "Y" type pipe circulation nonlinear state and observation equation at the current moment;

[0011] The double "Y" type tube circulation nonlinear state and observation equations are linearized to obtain the double "Y" type tube circulation linear state and observation equations;

[0012] Discretize the current dual "Y" tube cyclic linear state and observation equations, construct the current state and observation matrix discrete equations, construct the random error model of the dual "Y" tube cyclic linear state and observation equations, and then establish the current Kalman filter correction prediction model;

[0013] The state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are calculated, and the real-time drilling data and the state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are input into the Kalman filter correction prediction model to finally obtain the well kick and well leakage prediction results.

[0014] The deep-water drilling leakage detection method is preferably a double "Y"-type pipe fluid mechanics model that assumes the formation to be the lower branch of the large "Y"-type pipe, the drill pipe to be the inlet branch of the large "Y"-type pipe, and the annulus wellbore to be the outlet branch of the large "Y"-type pipe; the booster pipeline is regarded as the inlet branch of the small "Y"-type pipe, the riser annulus is the outlet branch of the small "Y"-type pipe, and the wellbore below the mud line is regarded as the lower branch of the small "Y"-type pipe.

[0015] In the deepwater drilling leakage detection method, preferably, the large "Y"-shaped tube circulation nonlinear observation equation is as follows:

[0016]

[0017] Nonlinear state equation of large "Y" type tube circulation:

[0018]

[0019] Where: P p is the pump pressure; P f is the formation pressure; P fr is the pressure difference between formation pressure and bottom hole pressure; Pdr is the friction resistance of fluid flow in the wellbore drill pipe; P h V is the hydrostatic pressure of the fluid in the wellbore drill pipe; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q a is the outlet flow rate at the wellhead;

[0020] Γ a is the annular fluid momentum; I a is the total inertia coefficient of the annular fluid, Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rf is the formation fluid invasion resistance; P ra is the annular circulation pressure loss; P h is the annular drilling fluid column pressure.

[0021] In the deepwater drilling leakage detection method, preferably, the small "Y"-shaped tube circulation nonlinear observation equation is as follows:

[0022]

[0023] Small "Y" type tube circulation nonlinear state equation:

[0024]

[0025] Where: P z P is the booster pump pressure; rL The pressure inside the blowout preventer or at the bottom of the riser; P zyr P is the pressure difference between the pressure inside the BOP and the pressure injection point of the booster pipeline; rzy is the pressure loss in the booster pipeline; P zyh V is the static column pressure of the fluid in the booster pipeline; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q ra is the outlet flow rate of the riser annulus; Γ ra I is the fluid momentum in the riser annulus; ra is the total inertia coefficient of the fluid in the riser annulus, Q a is the annulus outlet flow rate; Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rra P is the circulating pressure loss in the riser; rh is the liquid column pressure in the riser; Γ ra Hydraulic momentum of the riser annulus.

[0026] The deepwater drilling leakage detection method preferably linearizes the large "Y"-shaped pipe circulation nonlinear state equation, and then:

[0027]

[0028] f(x) represents a function; δ represents the change of a physical quantity; a 11 ~a 33 are the matrix coefficients after linearization of the state equation.

[0029] The deepwater drilling leakage detection method preferably linearizes the large "Y"-shaped pipe circulation nonlinear observation equation, and then:

[0030]

[0031] Where z is the observation vector; b 11 ~b 33 is the matrix coefficient of the linearized observation equation.

[0032] In the deepwater drilling leakage detection method, preferably, the drilling data includes pump pressure, pump pressure of the booster pump, drilling fluid flow at the riser, outlet flow and mud pool increment.

[0033] A second aspect of the present invention provides a deepwater drilling leakage detection device, comprising:

[0034] The first processing unit is used to establish a double "Y" type pipe fluid mechanics model of deepwater drilling wellbore-formation-watertight pipe booster pipeline coupled flow;

[0035] The second processing unit is used to obtain the drilling data at the current moment, filter and process the data and import them into the double "Y" type pipe fluid mechanics model, so as to determine the basic information of the reservoir and wellbore under the drilling state at the current moment;

[0036] The third processing unit is used to input the data including wellbore and formation related parameters and drilling fluid basic parameters at the current moment into the double "Y" type tube fluid mechanics model based on the previous geological condition exploration data and real-time drilling data, calculate the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient at the current moment, so as to establish the double "Y" type tube circulation nonlinear state and observation equation at the current moment;

[0037] The fourth processing unit is used to perform linearization processing on the double "Y" type tube circulation nonlinear state and observation equation to obtain the double "Y" type tube circulation linear state and observation equation;

[0038] The fifth processing unit is used to discretize the double "Y" type tube cyclic linear state and observation equations at the current moment, construct the state and observation matrix discrete equations at the current moment, construct the random error model of the double "Y" type tube cyclic linear state and observation equations, and then establish the Kalman filter correction prediction model at the current moment;

[0039] The sixth processing unit calculates the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation, and inputs the real-time drilling data and the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation into the Kalman filter correction prediction model, and finally obtains the well kick and well leakage prediction results.

[0040] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of any one of the above-mentioned deepwater drilling leakage detection methods.

[0041] A fourth aspect of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of any one of the above-mentioned deepwater drilling leakage detection methods are implemented.

[0042] The present invention adopts the above technical solution, which has the following advantages:

[0043] The leakage detection method of the present invention mainly relies on the change rules of the following three types of sensor parameters in the wellbore during the process of formation fluid invasion or drilling fluid leakage to comprehensively judge the leakage status in the wellbore, which are: (1) the change rules of the drilling pump pressure and outlet flow rate; (2) the flow velocity of the mixture of drilling fluid and formation invading fluid in the watertight pipe collected at the mudline position; (3) the pump pressure of the booster pump. By using the different combinations of the change rules of the above three types of data during the overflow and leakage process, the overflow and leakage status of the wellbore can be judged. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A diagram of a double "Y" type pipe fluid mechanics model of coupled flow of a deepwater drilling wellbore-formation-watertight pipe booster pipeline provided by an embodiment of the present invention;

[0045] Figure 2 A schematic diagram showing the increase in the drilling pump pressure, the increase in the booster pump pressure and the increase in the increase in the pressure at the bottom of the well caused by the initial overflow provided by the embodiment of the present invention;

[0046] Figure 3 It is a schematic diagram comparing the drilling fluid flow rate in the riser at the mudline position at the initial stage of bottom well overflow and the drilling fluid return rate at the riser annulus outlet provided by this embodiment of the present invention;

[0047] Figure 4 It is a schematic diagram comparing the change trends of the drilling pump pressure drop and the booster pump pressure stabilization caused by the gas migration to the expansion position after the bottom hole overflows provided by the embodiment of the present invention;

[0048] Figure 5 It is a schematic diagram comparing the drilling fluid flow rate in the riser at the mudline position and the drilling fluid return rate at the riser annulus outlet after the gas migrates to the expansion position after the bottom hole overflows provided by the embodiment of the present invention;

[0049] Figure 6 It is a schematic diagram comparing the change trends of the drilling pump pressure drop and the booster pump pressure stabilization caused by the gas migration to the riser area after the bottom hole overflow occurs provided by this embodiment of the present invention;

[0050] Figure 7 It is a schematic diagram comparing the drilling fluid flow rate in the riser at the mudline position and the drilling fluid return rate at the riser annulus outlet after the gas migrates to the riser area after the bottom hole overflows provided by this embodiment of the present invention;

[0051] Figure 8 It is a schematic diagram of the coupled flow of the deepwater drilling wellbore-formation-rise pressure boosting pipeline provided by this embodiment of the present invention;

[0052] Fig. 9 is a flow chart of a discrete Kalman filter prediction model provided by this embodiment of the present invention;

[0053] Fig.10 It is a flow analysis diagram of the early prediction model of well kick provided by this embodiment of the present invention (ie, a flow analysis diagram of the double “Y” type pipe fluid mechanics model). DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work are within the scope of protection of the present invention.

[0055] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second", "third", "fourth" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0056] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside", "outside", "inner side", "outside", "below", "above", etc. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0057] The existing deepwater drilling overflow monitoring technology is based on the principle of volume expansion, that is, the formation fluid that invades the annulus expands in volume in the annulus, resulting in a decrease in the density of the mixed fluid in the annulus, forming a pressure difference in the "U"-shaped flow system composed of the drill string and the annulus, causing flow changes. This method easily causes a large amount of formation fluid to enter the watertight pipe, making platform disposal difficult and risky. Therefore, conventional overflow monitoring methods can no longer meet the needs of early monitoring of deepwater drilling overflows.

[0058] How to identify the invading fluid before its volume expands, avoid the formation of solid hydrates after the gas enters the underwater blowout preventer, causing the blowout preventer to fail, and control the volume of gas entering the riser to a minimum, is extremely important for deepwater drilling overflow monitoring.

[0059] In view of the above technical problems, the present invention provides a deepwater drilling leakage detection method, which mainly relies on the change rules of the following three types of sensor parameters in the wellbore during the process of formation fluid invasion or drilling fluid leakage to comprehensively judge the leakage status in the wellbore, namely: (1) the change rules of the drilling pump pressure and outlet flow rate; (2) the flow velocity of the mixture of drilling fluid and formation invading fluid in the watertight pipe collected at the mudline position; (3) the pump pressure of the booster pump. By using the different combinations of the change rules of the above three types of data during the overflow and leakage process, the overflow and leakage status in the well can be judged.

[0060] This application first introduces the changing rules of key parameters in different stages of well kick and well leakage, as follows:

[0061] (1) Changes of key parameters at different stages of well kick

[0062] In the early stage of well kick: the invading fluid mixes with the drilling fluid in the original annulus (including the dissolution process) and migrates upward. In the early stage of migration, it is mainly concentrated in the bottom hole area and the density of the invading fluid is relatively high, so it causes flow disturbance to the fluid in the annulus and pressure disturbance to the fluid in the drill string. These disturbances are manifested as an increase in the outlet flow rate and a slight increase in the pump pressure of the drilling pump and the booster pump. Since the riser annulus area is large, the increase in the riser annulus circulation pressure loss caused by the increase in flow rate is much smaller than the increase in the circulation pressure loss in the entire annulus. Therefore, the increase in the drilling pump pressure is greater than the increase in the booster pump pressure.

[0063] Invading fluid migration rising period: As the pressure on the invading fluid gradually decreases, the density of the invading fluid decreases and the volume expands, the dissolved gas in the drilling fluid precipitates, causing the pressure of the annular liquid column to decrease. There is a density difference between the fluid in the drill string and the annulus, causing the drilling pump pressure to decrease. However, at this time, the invading fluid has not yet entered the riser, so the booster pump pressure will not decrease.

[0064] During the migration of the invading fluid to the mud line on the seabed: When the invading fluid migrates to the vicinity of the mud line, the flow velocity of the mixture of drilling fluid and formation invading fluid in the riser collected at the mud line position will increase (including the increasing velocity of particles and bubbles); but at this time, the fluid density in the riser annulus decreases, causing the booster pump pressure to decrease.

[0065] Based on the above three situations, the state and location of deepwater drilling overflow can be comprehensively judged.

[0066] (2) Changes of three key parameters at different stages of lost circulation

[0067] Well leakage occurs when drilling encounters abnormally low-pressure formations, and drilling fluid enters the formation from the annular open hole section, causing the return rate of the drilling fluid to decrease or even the drilling fluid to be unable to return to the ground, and the annular liquid level to drop. Leakage can be divided into micro leakage, medium leakage, and large leakage. Micro leakage refers to the return displacement of drilling fluid being less than the total displacement of the drilling pump and the booster pump, but greater than the injection displacement of the drilling pump. Medium leakage refers to the return displacement of drilling fluid being less than the displacement of the drilling pump. Large leakage refers to the situation where there is no return of drilling fluid and the annular drilling fluid level drops.

[0068] In the case of small leakage, the pump pressure of the drilling pump and the booster pump are reduced, and the flow velocity of the mixture of drilling fluid and formation intrusion fluid in the watertight pipe collected at the seabed mud line is reduced (including the particle and bubble velocities are in an increasing state), and the total outlet flow is reduced.

[0069] In response to the medium leakage state, the pump pressure of the drilling pump and the booster pump are further reduced, and the flow velocity of the mixture of drilling fluid and formation intrusion fluid in the watertight pipe collected at the seabed mud line position is further reduced (including the particle and bubble velocities are in an increasing state), and the total outlet flow is reduced.

[0070] In the case of a large leak, the pump pressure of the drilling pump and the booster pump may drop to zero, and the flow velocity of the mixture of drilling fluid and formation intrusion fluid in the riser collected at the seabed mudline is converted into a downward velocity (including particle and bubble velocities are in an increasing state), and the total outlet flow is not displayed. When the riser liquid level stabilizes, the velocity returns to zero.

[0071] (3) Deepwater drilling leakage identification method based on drilling pump pressure, outlet flow, flow rate of the mixture in the riser at the mudline, and booster pump pressure

[0072] 1) Based on the comparison diagram of the increase in the drilling pump pressure and the booster pump pressure caused by the initial overflow at the bottom of the well, as well as the comparison diagram of the drilling fluid flow rate in the riser at the mud line position at the initial overflow at the bottom of the well and the drilling fluid return rate at the riser annulus outlet, as shown in the figure below: Figure 2 , 3 As shown, it is possible to determine the current overflow status and the approximate location of the invading fluid.

[0073] 2) A schematic diagram comparing the change trend of the drilling pump pressure drop and the booster pump pressure stability caused by the gas migration to the expansion position after the bottom hole overflows, and a schematic diagram comparing the drilling fluid flow rate in the riser at the mudline position and the drilling fluid return rate at the riser annulus outlet after the gas migration to the expansion position after the bottom hole overflows, such as Figure 4 , 5 As shown, it can be judged that the overflow has affected the annular liquid column pressure below the mud line and caused the vertical pressure to drop, but did not cause the annular liquid column pressure above the booster pump injection point, so the booster pump pressure did not drop.

[0074] 3) A schematic diagram comparing the change trend of the drilling pump pressure drop and the booster pump pressure stability caused by the gas migration to the riser area after the bottom hole overflows, and a schematic diagram comparing the drilling fluid flow rate in the riser at the mudline position and the drilling fluid return rate at the riser annulus outlet after the gas migration to the riser area after the bottom hole overflows, such as Figure 6 , 7 As shown, it can be judged that the overflow has entered the annulus of the watertight pipe and caused the pump pressure and the vertical pressure of the booster pump to enter the descending channel, and the outlet flow rate increased significantly.

[0075] like Figure 1 , 10 As shown, the deepwater drilling leakage detection method provided by the present invention includes the following specific steps:

[0076] A double "Y" type pipe fluid dynamics model for coupled flow of deepwater drilling wellbore-formation-riser booster pipeline is established;

[0077] Obtain the current drilling data, filter and process it and import it into the double "Y" tube fluid mechanics model to determine the basic information of the reservoir and wellbore under the current drilling status;

[0078] On the basis of the previous geological exploration data and real-time drilling data, the data including the wellbore and formation related parameters and the basic parameters of the drilling fluid are input into the double "Y" type pipe fluid mechanics model at the current moment, and the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient are calculated at the current moment, so as to establish the double "Y" type pipe circulation nonlinear state and observation equation at the current moment;

[0079] The double "Y" type tube circulation nonlinear state and observation equations are linearized to obtain the double "Y" type tube circulation linear state and observation equations;

[0080] Discretize the current dual "Y" tube cyclic linear state and observation equations, construct the current state and observation matrix discrete equations, construct the random error model of the dual "Y" tube cyclic linear state and observation equations, and then establish the current Kalman filter correction prediction model;

[0081] The state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are calculated, and the real-time drilling data and the state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are input into the Kalman filter correction prediction model to finally obtain the well kick prediction results.

[0082] Specifically, Figure 1 , 8 As shown in the figure, the deepwater drilling wellbore-formation-waterproof pipe booster pipeline coupled flow double "Y" type pipe fluid mechanics model assumes the formation as the lower branch of the large "Y" type pipe, the drill pipe as the inlet branch of the large "Y" type pipe, and the annulus wellbore as the outlet branch of the large "Y" type pipe. The flow direction of the fluid in the lower branch of the "Y" type pipe is set to change according to the bottom hole pressure difference and the formation type. The model has three control bodies: fluid in the drill string, fluid in the annulus, and fluid in the formation. The booster pipeline is regarded as the inlet branch of the small "Y" type pipe, the riser annulus is regarded as the outlet branch of the small "Y" type pipe, and the wellbore below the mud line is regarded as the lower branch of the small "Y" type pipe.

[0083] The nonlinear state equation of the flow system is established based on the two Y-tubes:

[0084] 1) Large “Y” type tube circulation observation equation:

[0085]

[0086] 2) Large “Y” type tube circulation state equation

[0087]

[0088] Where: P p is the pump pressure; P f is the formation pressure; P fr is the pressure difference between formation pressure and bottom hole pressure; P b is the casing pressure; P dr is the friction resistance of fluid flow in the wellbore drill pipe; P h V is the hydrostatic pressure of the fluid in the wellbore drill pipe; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q a is the outlet flow rate at the wellhead; Γ a is the annular fluid momentum; I a is the total inertia coefficient of the annular fluid, Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rf is the formation fluid invasion resistance; P ra is the annular circulation pressure loss; P h is the annular drilling fluid column pressure.

[0089] 3) Small "Y" type tube circulation observation equation:

[0090]

[0091] 4) Small "Y" tube circulation state equation

[0092]

[0093] Where: P z P is the booster pump pressure; rL Pressure inside the blowout preventer; P zyr P is the pressure difference between the pressure inside the BOP and the pressure injection point of the booster pipeline; rzy is the pressure loss in the booster pipeline; P zyh V is the static column pressure of the fluid in the booster pipeline; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q ra is the outlet flow rate of the riser annulus; Γ ra I is the fluid momentum in the riser annulus; rais the total inertia coefficient of the fluid in the riser annulus; Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rra P is the circulating pressure loss in the riser; rh is the liquid column pressure in the riser; Γ ra Hydraulic momentum of the riser annulus.

[0094] The flow state estimation method is established for the nonlinear state equations of the above flow systems. The specific steps are as follows, taking a large "Y"-shaped pipe as an example:

[0095] 1) Linearize the state equation;

[0096] 2) Linearize the observation equation;

[0097] 3) The extended Kalman filter prediction method is used to make real-time predictions of the coupled flow state of the wellbore and formation.

[0098] 4) Assuming the state variable x(t) to be the change in the pressure difference between the wellbore and the formation, the change in the momentum of the wellbore annulus and the change in the mass of the annular fluid, the state equation of the state space model of the coupled flow system of the drilling wellbore and the formation is linearized by using the Taylor series expansion method, and then:

[0099]

[0100] f(x) represents a function; δ represents the change of a physical quantity; a 11 ~a 33 is the matrix coefficient after linearization of the state equation;

[0101] The observation equation is linearized in the same way, that is, the observation equation of the state space model of the coupled flow system of the wellbore and the formation is linearized by using the Taylor series expansion method, and the linearized equation is as follows:

[0102]

[0103] Where z is the observation vector; b 11 ~b 33 is the matrix coefficient of the linearized observation equation.

[0104] like Fig. 9 As shown in the figure, the calculation process of the well kick prediction and pressure feedback control model based on discrete Kalman filtering is as follows:

[0105] ① Preliminary prediction of the state quantity at time n

[0106] x n (-)=A d x n-1 (+)

[0107] Among them, x n (-) represents the initial predicted state quantity at time n, dimensionless; A d represents the state transfer matrix; x n-1 (+) is the corrected predicted state quantity at time n-1, dimensionless.

[0108] ② Preliminary prediction of the covariance transfer matrix at time n

[0109] P n (-)=A d P n-1 (+)A d T +Q n-1

[0110] Among them, Q n-1 represents the state error covariance matrix at time n-1; P n (-) represents the covariance transfer matrix of the predicted state vector at time n; P n-1 (+) represents the covariance matrix of the state vector at time n-1; A d T represents the state transition matrix.

[0111] ③Calculate the Kalman gain at time n

[0112]

[0113] Among them, K n represents the Kalman gain at time n; H n is the observation matrix or transformation matrix; R n is the positive definite variance matrix of the system measurement (observation equation) noise;

[0114] ④ Correct the predicted state quantity at time n

[0115] x n (+) = x n (-)+K n [z n -H n x n (-)]

[0116] Among them, x n (+) is the corrected predicted state quantity at time n, dimensionless; z n is the observed variable at time k;

[0117] ⑤Correct the prediction covariance transfer matrix at time n

[0118] P n (+)=(IK n Hn ) n (-)(IK n H n ) T +K n R n K n T Where I is the identity matrix; P n (+) represents the covariance transfer matrix at time n; K n T Represents the Kalman gain at time n.

[0119] The real-time wellbore flow parameter state quantity is predicted according to the time of the real-time drilling data point, that is, a set of real-time drilling data can be measured to predict a set of state quantities. The state quantity is filtered and corrected and predicted by combining the hydraulic parameter model (double "Y" type pipe fluid mechanics model) and random error model (random error model of double "Y" type pipe cyclic linear state and observation equation) established above. The specific discrete Kalman filter prediction process is as follows: Fig. 9 shown.

[0120] The input quantity calculated by the double "Y" type tube fluid mechanics model of the present invention is the observation data. As discussed above, the observation data selects the pump pressure, the pump pressure of the booster pump, the drilling fluid flow at the riser, the outlet flow and the mud pool increment in the real-time drilling data as the input quantity. The output quantity is the predicted state quantity obtained by this method, namely the formation pressure, the wellbore annulus momentum and the predicted mud pool increment. The observation data is input into the prediction model after data screening and processing, and then linearized and discretized, and then the parameters of the wellbore hydraulic model (double "Y" type tube fluid mechanics model) are calculated and the discrete Kalman filter is used for correction prediction, and finally the state prediction quantity is obtained.

[0121] A second aspect of the present invention provides a deepwater drilling leakage detection device, comprising:

[0122] The first processing unit is used to establish a double "Y" type pipe fluid mechanics model of deepwater drilling wellbore-formation-watertight pipe booster pipeline coupled flow;

[0123] The second processing unit is used to obtain the drilling data at the current moment, filter and process the data and import them into the double "Y" type pipe fluid mechanics model, so as to determine the basic information of the reservoir and wellbore under the drilling state at the current moment;

[0124] The third processing unit is used to input the data including wellbore and formation related parameters and drilling fluid basic parameters at the current moment into the double "Y" type tube fluid mechanics model based on the previous geological condition exploration data and real-time drilling data, calculate the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient at the current moment, so as to establish the double "Y" type tube circulation nonlinear state and observation equation at the current moment;

[0125] The fourth processing unit is used to perform linearization processing on the double "Y" type tube circulation nonlinear state and observation equation to obtain the double "Y" type tube circulation linear state and observation equation;

[0126] The fifth processing unit is used to discretize the double "Y" type tube cyclic linear state and observation equations at the current moment, construct the state and observation matrix discrete equations at the current moment, construct the random error model of the double "Y" type tube cyclic linear state and observation equations, and then establish the Kalman filter correction prediction model at the current moment;

[0127] The sixth processing unit calculates the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation, and inputs the real-time drilling data and the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation into the Kalman filter correction prediction model, and finally obtains the well kick and well leakage prediction results.

[0128] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of any one of the above-mentioned deepwater drilling leakage detection methods.

[0129] A fourth aspect of the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of any one of the above-mentioned deepwater drilling leakage detection methods are implemented.

[0130] The present invention is described in terms of flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to specific embodiments. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0131] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0132] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A deepwater drilling leak detection method, characterized in that: include: Establish a double "Y" type pipe fluid dynamics model for coupled flow of deepwater drilling wellbore-formation-riser booster pipeline; Obtain the current drilling data, filter and process it and import it into the double "Y" tube fluid mechanics model to determine the basic information of the reservoir and wellbore under the current drilling status; On the basis of the previous geological exploration data and real-time drilling data, the data including the wellbore and formation related parameters and the basic parameters of the drilling fluid are input into the double "Y" type pipe fluid mechanics model at the current moment, and the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient are calculated at the current moment, so as to establish the double "Y" type pipe circulation nonlinear state and observation equation at the current moment; The double "Y" type tube circulation nonlinear state and observation equations are linearized to obtain the double "Y" type tube circulation linear state and observation equations; Discretize the current dual "Y" tube cyclic linear state and observation equations, construct the current state and observation matrix discrete equations, construct the random error model of the dual "Y" tube cyclic linear state and observation equations, and then establish the current Kalman filter correction prediction model; The state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are calculated, and the real-time drilling data and the state and observation coefficient matrices of the double "Y" type tube circulation linear state and observation equations are input into the Kalman filter correction prediction model to finally obtain the well kick and lost circulation prediction results.

2. The deepwater drilling leakage detection method according to claim 1, characterized in that: The double "Y"-type pipe fluid mechanics model assumes that the formation is the lower branch of the large "Y"-type pipe, the drill pipe is assumed to be the inlet branch of the large "Y"-type pipe, and the annulus wellbore is assumed to be the outlet branch of the large "Y"-type pipe; the booster pipeline is regarded as the inlet branch of the small "Y"-type pipe, the riser annulus is regarded as the outlet branch of the small "Y"-type pipe, and the wellbore below the mud line is regarded as the lower branch of the small "Y"-type pipe.

3. The deepwater drilling leakage detection method according to claim 2, characterized in that: The nonlinear observation equation of the large "Y" tube cycle is as follows: Nonlinear state equation of large "Y" tube circulation: Where: P p is the pump pressure; P f is the formation pressure; P fr is the pressure difference between formation pressure and bottom hole pressure; P b is the casing pressure; P dr is the friction resistance of fluid flow in the wellbore drill pipe; P h V is the hydrostatic pressure of the fluid in the wellbore drill pipe; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q a is the outlet flow rate at the wellhead; Γ a is the annular fluid momentum; I a is the total inertia coefficient of the annular fluid, Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rf is the formation fluid invasion resistance; P ra is the annular circulation pressure loss; P h is the annular drilling fluid column pressure.

4. The deepwater drilling leakage detection method according to claim 3, characterized in that: The nonlinear observation equation of the small "Y" tube cycle is as follows: Nonlinear state equation of small "Y" tube circulation: Where: P z P is the booster pump pressure; rL Pressure inside the blowout preventer; P zyr P is the pressure difference between the pressure inside the BOP and the pressure injection point of the booster pipeline; rzy is the pressure loss in the booster pipeline; P zyh V is the static column pressure of the fluid in the booster pipeline; t is the total volume of the mud pool; V m is the standard volume of the mud pool; V n is the volume change of the mud pool, Q ra is the outlet flow rate of the riser annulus; Γ ra I is the fluid momentum in the riser annulus; ra is the total inertia coefficient of the fluid in the riser annulus, Q a is the annulus outlet flow rate; Q p is the flow rate at the drill pipe inlet, Q r is the displacement of the booster pump; P rra P is the circulating pressure loss in the riser; rh is the liquid column pressure in the riser; Γ ra Hydraulic momentum of the riser annulus.

5. The deepwater drilling leakage detection method according to claim 4, characterized in that: The linearization of the nonlinear state equation of the large "Y" tube cycle gives: f(x) represents a function; δ represents the change of a physical quantity; a 11 ~a 33 are the matrix coefficients after linearization of the state equation.

6. The deepwater drilling leakage detection method according to claim 5, characterized in that: Linearize the nonlinear observation equation of the large "Y" tube circulation, and we have: Where z is the observation vector; b 11 ~b 33 is the matrix coefficient of the linearized observation equation.

7. The deepwater drilling leakage detection method according to claim 1, characterized in that: The drilling data include pump pressure, booster pump pressure, drilling fluid flow at the riser, outlet flow and mud pool increment.

8. A deepwater drilling leakage detection device, characterized in that: include: The first processing unit is used to establish a double "Y" type pipe fluid mechanics model of deepwater drilling wellbore-formation-watertight pipe booster pipeline coupled flow; The second processing unit is used to obtain the drilling data at the current moment, filter and process the data and import it into the double "Y" type pipe fluid mechanics model, so as to determine the basic information of the reservoir and wellbore under the drilling state at the current moment; The third processing unit is used to input data including wellbore and formation related parameters and drilling fluid basic parameters at the current moment into the double "Y" type pipe fluid mechanics model based on the previous geological condition exploration data and real-time drilling data, calculate the flow resistance parameters between the reservoir and the wellbore, the wellbore circulation pressure loss parameters and the wellbore annulus fluid inertia coefficient at the current moment, so as to establish the double "Y" type pipe circulation nonlinear state and observation equation at the current moment; The fourth processing unit is used to perform linearization processing on the double "Y" type tube circulation nonlinear state and observation equation to obtain the double "Y" type tube circulation linear state and observation equation; The fifth processing unit is used to discretize the double "Y" type tube cyclic linear state and observation equations at the current moment, construct the state and observation matrix discrete equations at the current moment, construct the random error model of the double "Y" type tube cyclic linear state and observation equations, and then establish the Kalman filter correction prediction model at the current moment; The sixth processing unit calculates the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation, and inputs the real-time drilling data and the state and observation coefficient matrix of the double "Y" type tube circulation linear state and observation equation into the Kalman filter correction prediction model, and finally obtains the well kick and well leakage prediction results.

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 deepwater drilling leakage detection method according to any one of claims 1 to 7 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the deepwater drilling leakage detection method according to any one of claims 1 to 7 are implemented.

Images