A method, device, equipment and medium for constructing a multi-medium thermal conductivity model of a rock layer

Abstract

The present invention discloses a method, device, equipment and medium for constructing a multi-medium thermal conductivity model of a rock layer, including: determining the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity; constructing a mixed medium model of a wind-blown sand rock layer; determining the first thermal conductivity and the second thermal conductivity of the mixed medium model of a wind-blown sand rock layer according to the porosity, equivalent solid phase thermal conductivity, pore water ice phase thermal conductivity, gas phase thermal conductivity and the volume proportion of several regions in the mixed medium model of a wind-blown sand rock layer; determining the three-phase thermal conductivity according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow and the volume proportion of the pore structure perpendicular to the heat flow. The present invention belongs to the field of rock roadbed. The present invention can solve the problem that the thermal conductivity of the rock roadbed is difficult to determine after the rock roadbed is blocked by aeolian sand.

Description

Technical Field

[0001] The invention relates to the technical field of block stone roadbed, and in particular to a method, device, equipment and medium for constructing a multi-medium thermal conductivity model of a block stone layer. Background Art

[0002] The block rock embankment uses forced or natural convection to "actively cool" the embankment temperature (Cheng et al., 2007; Lai et al., 2014), and is widely used in China, Canada, the United States and other places (Darrow and Jensen, 2016; Lv et al., 2024; M-Lepage et al., 2012; Xu and Goering, 2008), which is conducive to the stable storage of underlying permafrost (Chen et al., 2018). The field monitoring data of the Qinghai-Tibet Railway for 11 consecutive years show that the block rock embankment has stable and continuous cooling performance and excellent engineering effect (Luo et al., 2018).

[0003] When faced with the invasion of aeolian sand, it will block the block stone roadbed and reduce its cooling performance, and it has become a prominent problem as desertification intensifies. The heat conduction path of the mixed medium of aeolian sand and block stone layer formed after the aeolian sand invades the block stone layer is complex and changeable. On the basis of considering the three phases of air, water, and ice, it is also necessary to study the thermal conductivity of the two mixed media with very different permeability, aeolian sand and block stone. As a result, the evaluation of the change in cooling performance after the aeolian sand invades the block stone roadbed lacks thermophysical parameters and has long relied on empirical value calculations. Therefore, how to more accurately determine the thermal conductivity of aeolian sand after it invades the block stone roadbed is an urgent problem to be solved. Summary of the invention

[0004] The embodiments of the present application provide a method, device, equipment and medium for constructing a multi-medium thermal conductivity model of a rubble layer, thereby solving the technical problem in the prior art that it is difficult to determine the thermal conductivity of a rubble roadbed after aeolian sand blocks the rubble roadbed, and achieving the technical effect of more accurately determining the thermal conductivity of aeolian sand invading the rubble roadbed.

[0005] In a first aspect, the present application provides a method for constructing a multi-medium thermal conductivity model of a blocky layer, the method comprising:

[0006] Determine the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity;

[0007] A mixed medium model of a wind-blown sand-rock layer is constructed, wherein the mixed medium model of a wind-blown sand-rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand-rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand-rock layer;

[0008] According to the porosity, equivalent solid phase thermal conductivity, pore water ice phase thermal conductivity, gas phase thermal conductivity and volume proportion of several regions in the mixed medium model of the wind-blown sand and rock layer, the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow and the second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow are determined respectively;

[0009] The three-phase thermal conductivity of the mixed medium model of the aeolian sand and rock layer is determined according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow, and the volume proportion of the pore structure perpendicular to the heat flow.

[0010] Furthermore, the first thermal conductivity of the mixed medium model of the aeolian sand and rock layer is determined when the pore structure is parallel to the heat flow, including:

[0011] According to the porosity, equivalent solid thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity, volume proportion of the first region and volume proportion of the second region of the mixed medium model of the wind-blown sand and rock layer, the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow is determined, and the sum of the volume proportion of the first region and the volume proportion of the second region is 1.

[0012] Furthermore, the formula of the first thermal conductivity includes:

[0013]

[0014] Among them, λ I is the first thermal conductivity, Sr1 is the volume ratio of the first region, 1-Sr1 is the volume ratio of the second region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

[0015] Furthermore, the second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer is determined when the pore structure is perpendicular to the heat flow, including:

[0016] According to the porosity, equivalent solid thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity, volume proportion of the third region and volume proportion of the fourth region of the mixed medium model of the wind-blown sand and rock layer, it is determined that when the pore structure is perpendicular to the heat flow, the sum of the second thermal conductivity, the volume proportion of the third region and the volume proportion of the fourth region of the mixed medium model of the wind-blown sand and rock layer is 1.

[0017] Furthermore, the formula of the second thermal conductivity includes:

[0018]

[0019] Among them, λ Π is the second thermal conductivity, Sr3 is the volume proportion of the third region, 1-Sr3 is the proportion of the fourth region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

[0020] Furthermore, the formula for the three-phase thermal conductivity of the mixed medium model of the wind-blown sand and rock layer includes:

[0021] λ=mλ I +(1-m)λ Π

[0022] λ Π is the second thermal conductivity, λ I is the first thermal conductivity, m is the volume fraction of the pore structure parallel to the heat flow, 1-m is the volume fraction of the pore structure perpendicular to the heat flow, and λ is the three-phase thermal conductivity of the mixed medium model of the wind-blown sandstone layer.

[0023] Furthermore, the equivalent solid phase thermal conductivity includes:

[0024] The boulders in the equivalent solid phase are regarded as dispersed phases, and the aeolian sand is regarded as continuous phases, and the dispersed phase and the continuous phase satisfy X 分散 +X 连续 =1;

[0025] When the equivalent solid phase satisfies X 分散 +X 连续 =1, the equivalent solid phase thermal conductivity is:

[0026]

[0027] Among them, λ c is the equivalent solid thermal conductivity, λ s is the thermal conductivity of aeolian sand, λ r is the thermal conductivity of the block stone, v s is the volume percentage of aeolian sand, v r is the volume percentage of the stone.

[0028] In a second aspect, the present application provides a device for constructing a multi-medium thermal conductivity model of a blocky rock layer, the device comprising:

[0029] The first sub-coefficient module is used to determine the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity;

[0030] A construction module is used to construct a mixed medium model of a wind-blown sand-rock layer, wherein the mixed medium model of a wind-blown sand-rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand-rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand-rock layer;

[0031] The second sub-coefficient module is used to determine the first thermal conductivity of the mixed medium model of the wind-blown sandstone layer when the pore structure is parallel to the heat flow, and to determine the second thermal conductivity of the mixed medium model of the wind-blown sandstone layer when the pore structure is perpendicular to the heat flow, according to the porosity, equivalent solid thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity and volume proportion of several regions in the mixed medium model of the wind-blown sandstone layer;

[0032] The three-phase thermal conductivity module is used to determine the three-phase thermal conductivity of the mixed medium model of the wind-blown sand and rock layer according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow, and the volume proportion of the pore structure perpendicular to the heat flow.

[0033] In a third aspect, the present application provides an electronic device, including:

[0034] processor;

[0035] a memory for storing processor-executable instructions;

[0036] The processor is configured to execute to implement a method for constructing a multi-medium thermal conductivity model of a block stone layer as provided in the first aspect.

[0037] In a fourth aspect, the present application provides a non-temporary computer-readable storage medium. When the instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to implement a method for constructing a multi-medium thermal conductivity model of a block stone layer as provided in the first aspect.

[0038] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0039] The present application provides a method for constructing a multi-medium thermal conductivity model of a rock layer, comprising: determining an equivalent solid phase thermal conductivity and a pore water ice phase thermal conductivity; constructing a mixed medium model of a sandy rock layer, wherein the mixed medium model of a sandy rock layer includes a plurality of pore structures, the mixed medium model of a sandy rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is uniformly distributed in the mixed medium model of a sandy rock layer; determining an equivalent solid phase thermal conductivity and a pore water ice phase thermal conductivity of the mixed medium model of a sandy rock layer according to the porosity, the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity of the mixed medium model of a sandy rock layer; determining a multi-medium thermal conductivity ... The thermal coefficient, gas phase thermal conductivity and the volume proportion of several areas in the mixed medium model of the wind-blown sand and rock layer respectively determine the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow, and determine the second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow; according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow and the volume proportion of the pore structure perpendicular to the heat flow, the three-phase thermal conductivity of the mixed medium model of the wind-blown sand and rock layer is determined. This application solves the problem of lack of thermal conductivity in the quantitative evaluation and predictive analysis of the cooling performance of the block stone roadbed after being invaded by aeolian sand by establishing a mixed medium model of the wind-blown sand and rock layer at the mesoscopic scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 A schematic diagram of a process for constructing a multi-medium thermal conductivity model of a block rock layer provided in this application;

[0042] Figure 2 A schematic diagram of the decomposition process of solving the first thermal conductivity provided in this application;

[0043] Figure 3 A schematic diagram of the decomposition process of solving the second thermal conductivity provided in the present application;

[0044] Figure 4 A schematic diagram of a device for constructing a multi-medium thermal conductivity model of a block rock layer provided in the present application;

[0045] Figure 5 The present application provides a schematic structural diagram of an electronic device.

[0046] Reference numerals

[0047] 1-equivalent solid phase, 2-pore water ice phase, 3-gas phase. DETAILED DESCRIPTION

[0048] The embodiment of the present application provides a method for constructing a multi-medium thermal conductivity model of a rubble layer, thereby solving the technical problem in the prior art that it is difficult to determine the thermal conductivity of a rubble roadbed when the rubble roadbed is blocked by wind-blown sand.

[0049] The technical solution of the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0050] A method for constructing a multi-medium thermal conductivity model of a rock layer, the method comprising: determining an equivalent solid phase thermal conductivity and a pore water ice phase thermal conductivity; constructing a mixed medium model of a sandy rock layer, wherein the mixed medium model of the sandy rock layer includes a plurality of pore structures, the mixed medium model of the sandy rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of the sandy rock layer; determining the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity of the mixed medium model of the sandy rock layer according to the porosity, the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity of ... , gas phase thermal conductivity and the volume proportion of several regions in the mixed medium model of wind-blown sand and rock layer, respectively determine the first thermal conductivity of the mixed medium model of wind-blown sand and rock layer when the pore structure is parallel to the heat flow, and determine the second thermal conductivity of the mixed medium model of wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow; according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow and the volume proportion of the pore structure perpendicular to the heat flow, determine the three-phase thermal conductivity of the mixed medium model of wind-blown sand and rock layer.

[0051] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0052] First of all, the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0053] This application provides Figure 1 A method for constructing a multi-medium thermal conductivity model of a blocky rock layer is shown, and the method includes steps S11-S14.

[0054] Step S11, determining the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity.

[0055] Step S12, constructing a mixed medium model of a wind-blown sand and rock layer, the mixed medium model of a wind-blown sand and rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand and rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand and rock layer.

[0056] Step S13, according to the porosity, equivalent solid phase thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity and volume proportion of several regions in the mixed medium model of the wind-sand-rock layer, respectively determine the first thermal conductivity of the mixed medium model of the wind-sand-rock layer when the pore structure is parallel to the heat flow, and determine the second thermal conductivity of the mixed medium model of the wind-sand-rock layer when the pore structure is perpendicular to the heat flow.

[0057] Step S14, determining the three-phase thermal conductivity of the mixed medium model of the wind-blown sand and rock layer according to the second thermal conductivity, the first thermal conductivity, the volume fraction of the pore structure parallel to the heat flow, and the volume fraction of the pore structure perpendicular to the heat flow.

[0058] It should be noted that in this application, the pore structure is regarded as uniformly distributed in the mixed medium model of the wind-blown sand and rock layer, and the pore structure is simplified to an equivalent solid phase, a pore water-ice phase, and a gas phase at a microscopic scale. The equivalent solid phase is composed of wind-blown sand and rock, the pore water-ice phase is regarded as water, ice, or a water-ice mixture at different temperatures, and the pore gas phase is air.

[0059] Regarding step S11, the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity are determined.

[0060] Determine the equivalent solid thermal conductivity

[0061] The boulders in the equivalent solid phase are regarded as dispersed phases, and the aeolian sand is regarded as continuous phases, and the dispersed phase and the continuous phase satisfy X 分散 +X 连续 =1.

[0062] When the equivalent solid phase satisfies X 分散 +X 连续 =1, the equivalent solid phase thermal conductivity is:

[0063]

[0064] Among them, λ c is the equivalent solid thermal conductivity, λ s is the thermal conductivity of aeolian sand, λ r is the thermal conductivity of the block stone, v s is the volume percentage of aeolian sand, v r is the volume percentage of the stone.

[0065]

Thermal conductivity of pore water ice phase

[0066] At around 0℃, the water-ice phase in the pore structure undergoes a water-ice phase transition, and ice begins to form in the pore structure below 0℃. When the temperature is below -1.0℃, the unfrozen water content tends to be stable. The formula for determining the volume content of unfrozen water can include:

[0067] χ=0.93H(TTref ,△T)+0.07

[0068] Where, χ is the unfrozen water content; T ref is the ice / water phase transition temperature, which can be taken as T in this application ref =0°C; △T is the phase transition temperature interval, which can be taken as 0.5°C in this application; H(TT ref ,△T) is the Heaviside function, where:

[0069]

[0070] Since the volume proportion of ice in the pore structure is high, the thermal conductivity of the pore water-ice phase is applicable to the thermal conductivity of binary composite materials at high filling rates, including:

[0071]

[0072] Among them, v i is the volume fraction of ice, λ iw is the thermal conductivity of the pore water ice phase, λ w is the thermal conductivity of water, which can be taken as w =0.6(W·m -1 ℃ -1 ); i is the thermal conductivity of ice, which can be taken as i =2.2(Wm -1 ℃ -1 ).

[0073] In addition, the gas phase in this application can take λ a =0.02(Wm -1 ℃ -1 ).

[0074] Regarding step S12, a mixed medium model of a wind-blown sand and rock layer is constructed, and the mixed medium model of a wind-blown sand and rock layer includes a plurality of pore structures. The mixed medium model of a wind-blown sand and rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand and rock layer.

[0075] In this application, the mixed medium model of wind-blown sand and rock layer is constructed as a cube structure, such as Figure 2 and Figure 3 As shown, Figure 2 (a) and (b) in Figure 3 The cubes in (f) and (g) are both mixed medium models of wind-blown sand and rock layers. In this application, the side length of the cube is set to 2b, where the heat flow flows from left to right (please refer to Figure 2 b).

[0076] In this application, the pore structure is divided into {pore structure parallel to heat flow} and {pore structure perpendicular to heat flow} for separate discussion. Figure 2 (a) and (b) are the cases where the pore structure is parallel to the heat flow. Figure 3 (f) and (g) show the situation where the pore structure is perpendicular to the heat flow.

[0077] Regarding step S13, according to the porosity, equivalent solid phase thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity and volume proportion of several regions in the mixed medium model of the wind-sand-rock layer, the first thermal conductivity of the mixed medium model of the wind-sand-rock layer is determined when the pore structure is parallel to the heat flow, and the second thermal conductivity of the mixed medium model of the wind-sand-rock layer is determined when the pore structure is perpendicular to the heat flow.

[0078]

About the first thermal conductivity

[0079] According to the porosity, equivalent solid thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity, volume proportion of the first region and volume proportion of the second region of the mixed medium model of the wind-blown sand and rock layer, the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow is determined, and the sum of the volume proportion of the first region and the volume proportion of the second region is 1.

[0080] Please combine Figure 2 Specifically, when the pore structure is parallel to the heat flow:

[0081] The origin is located at the center of the cube, the pore structure is parallel to the heat flow, and the pore structure is a cylindrical structure with a diameter of 2a. The cube unit body is cut into thin slices by a plane perpendicular to the x-axis (such as Figure 2 b), the thickness of the sheet is dy, the length and width are both 2b, and the radius of the pore structure in the middle is a.

[0082] like Figure 2 c Figure 2 (d) is a side view of (c)), in the first region ( Figure 2 The "①" in c in (1) is further divided by two planes perpendicular to the z-axis and with a distance dz, and the following is obtained: Figure 2 The calculation microelement small cuboid shown in (e) has a length of b, a width of dy, and a height of dz.

[0083] The thermal conductivity of the microelement small cuboid is:

[0084]

[0085] Among them, λ Y is the thermal conductivity of the microelement small cuboid, λ Fis the thermal conductivity of the dispersed phase, λ G is the thermal conductivity of the continuous phase solid phase, Where a is the radius of the pore structure, and z is the distance from the origin to the microelement cuboid in the z-axis direction.

[0086] The thermal conductivity of the infinitesimal cuboid in the first quadrant is the thermal conductivity of the entire sheet:

[0087]

[0088] Among them, λ B is the thermal conductivity of the infinitesimal cuboid.

[0089] When the heat flow direction is parallel to the y-axis, the thermal resistance of regions ① and ② is in series during the heat flow conduction process (i.e., the first region and the second region, please refer to Figure 2 b and Figure 2 c) According to the definition of thermal resistance and the relationship between series thermal resistance, when the pore structure is parallel to the heat flow, the first thermal conductivity of the mixed medium model of wind-blown sand and rock layer is:

[0090]

[0091] Among them, λ I is the first thermal conductivity, Sr1 is the volume ratio of the first region, 1-Sr1 is the volume ratio of the second region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

[0092]

About the second thermal conductivity

[0093] Based on the porosity, equivalent solid thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity, volume proportion of the third region and volume proportion of the fourth region of the mixed medium model of the wind-sand-rock layer, it can be determined that when the pore structure is perpendicular to the heat flow, the sum of the second thermal conductivity of the mixed medium model of the wind-sand-rock layer, the volume proportion of the third region and the volume proportion of the fourth region is 1.

[0094] Please refer to Figure 3 (f)-(j) are the same as when they are parallel to the heat flow direction, where the “division method of the third and fourth regions” is similar to the “division method of the first and second regions”, and the thermal conductivity of the entire sheet is:

[0095]

[0096] Where y is the distance from the origin to the microelement cuboid in the y-axis direction.

[0097] Due to the difference in thermal conductivity between the pore ice-water phase, the pore gas phase and the equivalent solid phase, obvious tortuosity occurs when the heat flow passes through the pores.

[0098] like Figure 3 As shown in j, Figure 3 The line segments in j represent the actual heat flow propagation path l e ,exist Figure 3 The path of some line segments that obviously exist in j is a curve, and θ is the contact angle between the heat flow line and the tangent line of the pore structure surface, which is given by Figure 3 jIt can be clearly seen that the actual heat flow propagation path l e It will change with the change of contact angle θ.

[0099] The apparent geometric thickness l = 2b, when the heat flow propagation path increases, its thermal resistance increases, among which the fourth area ( Figure 3 Thermal conductivity and tortuosity of "④" in i Inversely proportional.

[0100] Based on the integral averaging method, e By integrating in the range of (0, π / 2), we can obtain the equivalent actual heat flow propagation path, and then obtain the equivalent tortuosity, including:

[0101]

[0102] Among them, l e is the actual propagation path of heat flow, τ is the tortuosity, and θ is the contact angle.

[0103] like Figure 3 It can be seen that compared with the heat flow direction, the third area and the fourth area are in parallel relationship. According to the definition of thermal resistance and the properties of parallel thermal resistance, the effective thermal conductivity of the entire unit body is obtained, including:

[0104]

[0105] Among them, Srλ ③ is the thermal conductivity of the third region, (1-Sr)λ ④ is the thermal conductivity of the fourth region, λ π is the second thermal conductivity, Sr3 is the volume proportion of the third region, 1-Sr3 is the proportion of the fourth region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

[0106] Regarding step S14, the three-phase thermal conductivity of the wind-blown sand and rock layer mixed medium model is determined according to the second thermal conductivity, the first thermal conductivity, the volume fraction of the pore structure parallel to the heat flow, and the volume fraction of the pore structure perpendicular to the heat flow.

[0107] Since the pore structure is not completely parallel or perpendicular to the heat flow direction, in this application, the volume fraction parallel to the heat flow direction is assumed to be m, and the volume fraction perpendicular to the heat flow direction is assumed to be (1-m), and the three-phase thermal conductivity of the mixed medium model of the wind-blown sandstone layer can be obtained, including:

[0108]

[0109] Among them, λ Π is the second thermal conductivity, λ I is the first thermal conductivity, m is the volume fraction of the pore structure parallel to the heat flow, 1-m is the volume fraction of the pore structure perpendicular to the heat flow, and λ is the three-phase thermal conductivity of the mixed medium model of the wind-blown sandstone layer.

[0110] In summary, the present application provides a method for constructing a multi-medium thermal conductivity model of a rock layer, including: determining the equivalent solid-phase thermal conductivity and the pore water-ice phase thermal conductivity; constructing a mixed medium model of a sand-bloom layer, wherein the mixed medium model of a sand-bloom layer includes a plurality of pore structures, the mixed medium model of a sand-bloom layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is uniformly distributed in the mixed medium model of a sand-bloom layer; according to the porosity, equivalent solid-phase thermal conductivity, pore water-ice phase thermal conductivity of the mixed medium model of a sand-bloom layer, The phase thermal conductivity, gas phase thermal conductivity and the volume proportion of several regions in the mixed medium model of wind-blown sand and rock layer respectively determine the first thermal conductivity of the mixed medium model of wind-blown sand and rock layer when the pore structure is parallel to the heat flow, and determine the second thermal conductivity of the mixed medium model of wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow; according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow and the volume proportion of the pore structure perpendicular to the heat flow, the three-phase thermal conductivity of the mixed medium model of wind-blown sand and rock layer is determined. This application solves the problem of lack of thermal conductivity in quantitative evaluation and predictive analysis of cooling performance of block stone roadbed after invasion of aeolian sand by establishing a mixed medium model of wind-blown sand and rock layer at the mesoscopic scale.

[0111] In addition, this application clarifies the effects of sand content, moisture content of aeolian sand, porosity, and temperature on the prediction of thermal conductivity of the meso-scale model, and derives the relationship and range of influencing factors, including: the heat flux density and temperature difference of the mixed medium of aeolian sand and rock layer fluctuate with the temperature cycle, the heat conduction path and contact change due to the liquid bridge effect, the thermal conductivity conditionally fluctuates with the temperature cycle, and is positively correlated with the moisture content. The lower the moisture content, the smaller the impact.

[0112] The mixed medium model of the wind-blown sand and rock layer provided in this application further considers the direction of heat flow and divides the mixed medium of the wind-blown sand and rock layer into a three-phase mixture. For composite systems with large differences in thermal conductivity among highly dispersed phase, discrete phase and continuous phase, the heat conduction combination between different materials is considered more fully than other theoretical models, and the relative error is within 10% in both frozen and melted states.

[0113] The accuracy of the mixed medium model of each wind-blown sand and rock layer in the frozen state is 细观 >λ 几何 >λ EMT >λ HS小 >λ 并联 >λ HS大 >λ 串联 , the accuracy of the mixed medium model for each wind-blown sand and rock layer in the melting state is λ 细观 >λ 几何 >λ HS小 >λ EMT >λ 并联 >λ HS大 >λ 串联 .

[0114] This application also changes the influencing factors to obtain the thermal conductivity range of the wind-sand-rock layer mixed medium model under different variables, and calculates the influence of various influencing factors on the thermal conductivity according to the grey correlation degree, from large to small: sand content>porosity>water content>temperature.

[0115] Based on the same inventive concept, the present application provides Figure 4 A device for constructing a multi-medium thermal conductivity model of a block stone layer is shown, and the device comprises:

[0116] The first sub-coefficient module 41 is used to determine the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity;

[0117] A construction module 42 is used to construct a mixed medium model of a wind-blown sand-rock layer, wherein the mixed medium model of a wind-blown sand-rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand-rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand-rock layer;

[0118] The second sub-coefficient module 43 is used to determine the first thermal conductivity of the mixed medium model of the wind-sand-rock layer when the pore structure is parallel to the heat flow, and to determine the second thermal conductivity of the mixed medium model of the wind-sand-rock layer when the pore structure is perpendicular to the heat flow, according to the porosity, equivalent solid phase thermal conductivity, pore water-ice phase thermal conductivity, gas phase thermal conductivity and volume proportion of several regions in the mixed medium model of the wind-sand-rock layer;

[0119] The three-phase thermal conductivity module 44 is used to determine the three-phase thermal conductivity of the wind-sand-rock layer mixed medium model according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow, and the volume proportion of the pore structure perpendicular to the heat flow.

[0120] Based on the same inventive concept, the present application also provides Figure 5 An electronic device as shown includes:

[0121] Processor 51;

[0122] A memory 52 for storing instructions executable by the processor 51;

[0123] The processor 51 is configured to execute to implement a method for constructing a multi-medium thermal conductivity model of a block stone layer as provided above.

[0124] Based on the same inventive concept, the present application also provides a non-temporary computer-readable storage medium. When the instructions in the storage medium are executed by the processor 51 of the electronic device, the electronic device can execute a method for constructing a multi-medium thermal conductivity model of a block stone layer as provided above.

[0125] Since the electronic device introduced in this embodiment is an electronic device used to implement the information processing method in the embodiment of the present application, based on the information processing method introduced in the embodiment of the present application, a person skilled in the art can understand the specific implementation of the electronic device of the present embodiment and its various variations, so how the electronic device implements the method in the embodiment of the present application is not described in detail here. As long as a person skilled in the art implements the electronic device used by the information processing method in the embodiment of the present application, it belongs to the scope of protection of this application.

[0126] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0127] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. 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 produce 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.

[0128] 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.

[0129] 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.

[0130] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0131] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for constructing a multi-medium thermal conductivity model of a rock layer, characterized in that: The method comprises: Determine the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity; Constructing a mixed medium model of a wind-blown sand and rock layer, wherein the mixed medium model of a wind-blown sand and rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand and rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand and rock layer; According to the porosity of the mixed medium model of the wind-blown sand and rock layer, the equivalent solid phase thermal conductivity, the pore water-ice phase thermal conductivity, the gas phase thermal conductivity and the volume proportion of several regions in the mixed medium model of the wind-blown sand and rock layer, respectively determine the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow, and determine the second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow; The three-phase thermal conductivity of the wind-blown sand and rock layer mixed medium model is determined according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow, and the volume proportion of the pore structure perpendicular to the heat flow.

2. A method for constructing a multi-medium thermal conductivity model of a rock layer according to claim 1, characterized in that: The first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow is determined, including: According to the porosity of the mixed medium model of the wind-blown sand and rock layer, the equivalent solid-phase thermal conductivity, the pore water-ice phase thermal conductivity, the gas phase thermal conductivity, the volume proportion of the first region and the volume proportion of the second region, the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer is determined when the pore structure is parallel to the heat flow, and the sum of the volume proportion of the first region and the volume proportion of the second region is 1.

3. A method for constructing a multi-medium thermal conductivity model of a block rock layer as claimed in claim 2, characterized in that: The formula for the first thermal conductivity includes: Among them, λ I is the first thermal conductivity, Sr1 is the volume ratio of the first region, 1-Sr1 is the volume ratio of the second region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

4. A method for constructing a multi-medium thermal conductivity model of a rock layer according to claim 1, characterized in that: The second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow is determined, including: According to the porosity of the mixed medium model of the wind-blown sand and stone layer, the equivalent solid-phase thermal conductivity, the pore water-ice phase thermal conductivity, the gas phase thermal conductivity, the volume proportion of the third region and the volume proportion of the fourth region, it is determined that when the pore structure is perpendicular to the heat flow, the sum of the second thermal conductivity of the mixed medium model of the wind-blown sand and stone layer, the volume proportion of the third region and the volume proportion of the fourth region is 1.

5. A method for constructing a multi-medium thermal conductivity model of a block rock layer as claimed in claim 4, characterized in that: The formula for the second thermal conductivity includes: Among them, λ Π is the second thermal conductivity, Sr3 is the volume proportion of the third region, 1-Sr3 is the proportion of the fourth region, λ iw is the thermal conductivity of pore water ice phase, λ c is the equivalent solid thermal conductivity, n is the porosity of the mixed medium model of wind-blown sand and rock layer, λ a Gas phase thermal conductivity.

6. A method for constructing a multi-medium thermal conductivity model of a block rock layer as claimed in claim 1, characterized in that: The formula of the three-phase thermal conductivity of the mixed medium model of wind-blown sand and rock layer includes: λ=mλ I +(1-m)λ Π λ Π is the second thermal conductivity, λ I is the first thermal conductivity, m is the volume fraction of the pore structure parallel to the heat flow, 1-m is the volume fraction of the pore structure perpendicular to the heat flow, and λ is the three-phase thermal conductivity of the mixed medium model of the wind-blown sandstone layer.

7. The method for constructing a multi-medium thermal conductivity model of a rock layer according to claim 1, characterized in that: Equivalent solid thermal conductivity, including: The boulders in the equivalent solid phase are regarded as dispersed phases, and the aeolian sand is regarded as continuous phases, and the dispersed phase and the continuous phase satisfy X 分散 +X 连续 =1; When the equivalent solid phase satisfies X 分散 +X 连续 =1, the equivalent solid phase thermal conductivity is: Among them, λ c is the equivalent solid thermal conductivity, λ s is the thermal conductivity of aeolian sand, λ r is the thermal conductivity of the block stone, v s is the volume percentage of aeolian sand, v r is the volume percentage of the stone.

8. A device for constructing a multi-medium thermal conductivity model of a rock layer, characterized in that: The device comprises: The first sub-coefficient module is used to determine the equivalent solid phase thermal conductivity and the pore water ice phase thermal conductivity; A construction module is used to construct a mixed medium model of a wind-blown sand and rock layer, wherein the mixed medium model of a wind-blown sand and rock layer includes a plurality of pore structures, the mixed medium model of a wind-blown sand and rock layer is a cube structure, the pore structure is a cylindrical structure, and the pore structure is evenly distributed in the mixed medium model of a wind-blown sand and rock layer; The second sub-coefficient module is used to determine the first thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is parallel to the heat flow, and to determine the second thermal conductivity of the mixed medium model of the wind-blown sand and rock layer when the pore structure is perpendicular to the heat flow, according to the porosity of the mixed medium model of the wind-blown sand and rock layer, the equivalent solid phase thermal conductivity, the pore water-ice phase thermal conductivity, the gas phase thermal conductivity and the volume proportion of several regions in the mixed medium model of the wind-blown sand and rock layer; The three-phase thermal conductivity module is used to determine the three-phase thermal conductivity of the wind-sand-rock layer mixed medium model according to the second thermal conductivity, the first thermal conductivity, the volume proportion of the pore structure parallel to the heat flow, and the volume proportion of the pore structure perpendicular to the heat flow.

9. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute a method for constructing a multi-medium thermal conductivity model of a blocky layer as claimed in any one of claims 1 to 7.

10. A non-temporary computer-readable storage medium, when the instructions in the storage medium are executed by a processor of an electronic device, the electronic device can implement a method for constructing a multi-medium thermal conductivity model of a block rock layer as described in any one of claims 1 to 7.

Images