CFD (computational fluid dynamics)-based edible mushroom house environment regulation and control technical method

Abstract

The invention discloses an edible mushroom house environment regulation and control technical method based on CFD, and the method comprises the following steps: S1, carrying out the three-dimensional modeling of an edible mushroom house, and building a CFD flow field simulation model; s2, according to the test data of the environmental parameters of the edible mushroom house, pre-processing and setting boundary conditions of the mushroom house, and carrying out analog calculation on a plurality of indexes of the mushroom house; s3, performing result post-processing analysis through iterative operation by setting planar graphs of different heights and spatial orientations, and obtaining a distribution rule of the multiple indexes of the mushroom house in the space and time; and S4, performing ventilation effect analysis under common working conditions in summer so as to determine the position range of the parameter area which does not reach the standard. Effective suggestions and feedback can be provided for improving ventilation structure configuration of the edible mushroom house and optimizing a ventilation system, a good growth environment is provided for mushrooms, and high efficiency of production is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of building environment control, and in particular to a CFD-based edible mushroom house environment control technology method. Background Art

[0002] Edible fungi are delicious, low in calories, high in fiber, and have certain medicinal value, making them very popular. Mushroom cultivation houses can create environmental conditions suitable for their growth and meet their different needs for environmental conditions at different growth stages. With the development of large-scale production and factory production, the structure of mushroom cultivation houses has gradually become larger, placing higher requirements on ventilation components and control systems. If the ventilation system of mushroom houses is not designed properly, it will lead to poor air flow and uneven distribution of the internal environment, which will generate heat, water vapor and accumulation in the cultivation area, resulting in uneven growth of edible fungi and reduced quality and yield.

[0003] Therefore, it is urgent to provide a technical solution that can solve the problem of hot and humid environment in edible mushroom houses in the prior art. Summary of the invention

[0004] In view of this, the present invention provides a CFD-based environmental control technology method for edible mushroom houses.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A CFD-based edible mushroom house environment control technology method includes the following steps:

[0007] S1: Conduct 3D modeling of the edible mushroom house and establish a CFD flow field simulation model;

[0008] S2: According to the test data of the environmental parameters of the edible mushroom house, the boundary conditions of the mushroom house are pre-processed and set, and multiple indicators of the mushroom house are simulated and calculated;

[0009] S3: By setting plane diagrams of different heights and spatial orientations, performing post-processing analysis of the results through iterative calculations, the distribution patterns of multiple indicators of the mushroom house in time and space are obtained;

[0010] S4: Conduct ventilation effect analysis under common summer operating conditions to determine the location range of areas where parameters do not meet the standards.

[0011] Preferably, the method further includes using the open source software Blender to establish a simplified model and using the grid division plate provided by the open source OpenFOAM to grid the overall mushroom house model according to the principle of local to global; gridding the air supply duct, the exhaust duct and each wall surface of the mushroom house body respectively; setting the grid refinement level to 0-4 by comprehensively considering the performance and calculation accuracy of the computer; focusing on grid encryption processing for areas where the air flow field inside the mushroom house changes greatly, and obtaining 23965946 total grids.

[0012] Preferably, in said S1, the method for three-dimensional modeling of the edible mushroom house is: simplifying the three-dimensional modeling, ignoring the wall thickness of the mushroom house, simplifying some rounded corners in the geometric features of the mushroom house, considering the ventilation performance inside the mushroom house; ignoring the cultivation racks, lighting equipment, staff, and mechanical parts.

[0013] Preferably, in S2, the distribution of the ventilation holes and environmental parameter measurement points of the mushroom house is described as follows: 18 points are arranged indoors, of which 5 points are arranged under the first ventilation hole of the air inlet pipe, 5 points are arranged under the second ventilation hole, 4 points are arranged in the middle, 6 layers are missing, and these points are on the 2nd, 4th, 6th, 8th, and 10th layers, respectively at 0.8, 1.8, 2.8, 3.8, and 4.8 positions; these are all placed in the column of 14 points against the wall; and there are 4 points arranged in the middle column of mushrooms, 6 layers are missing, and they are placed in the middle column of mushrooms, about 20-30cm away from the passage.

[0014] Preferably, in said S2, the method for setting the boundary conditions of the mushroom house before processing is: setting the edible mushroom house model for internal flow field analysis; considering the effect of the gravity field when analyzing the humidity field, and calibrating the acceleration in the vertical direction of the three-dimensional model to -9.81m / s 2 , the acceleration in other directions is 0m / s 2 ; For the whole edible mushroom house wall condition, the wall temperature is set to a constant temperature, ignoring the wall roughness, and the wall temperature is stable at 20.2℃; the cooling source of the air cooler is set to 41955.08J / (m 3 ·s), the air cooler / turbine fan and humidifier are defined as momentum sources, with speeds of 11.11m / s and 2.3148m / s respectively; the air outlet is set to pressureInletOutletVelocity boundary condition; the p_rg pressure boundary condition is set to toTalPressure, and its value is set to 725pa; at the same time, the thermodynamic parameters and humidity parameters are set according to the measured temperatures at each air outlet, and the temperature values ​​of each measuring point are also used as reference temperatures; the flow field fluid is air, and the ventilation structure is optimized and adjusted based on the comparison of the temperature field and wind speed field obtained by simulation with the results measured on site.

[0015] Preferably, in S2, the multiple indicators of the mushroom house include: wind speed and temperature.

[0016] Preferably, in said S2, simulation calculation of multiple indicators of the mushroom house is performed through a group of control equations, specifically including a continuity equation, a momentum equation, an energy equation, a component transport equation and a standard k-ε turbulence model.

[0017] Preferably, the continuity equation comprises:

[0018]

[0019] Among them, u is the component of velocity in the x direction, v is the component of velocity in the y direction, and w is the component of velocity in the z direction;

[0020] The momentum equation includes:

[0021]

[0022] Among them, μ eff is the effective viscosity, T is the air temperature, T ref is the air reference temperature, P is the static pressure, ρ is the air density, g is the gravitational acceleration, and β is the air thermal expansion coefficient;

[0023] The energy equation includes:

[0024]

[0025] Where T is the air temperature, k is the heat transfer coefficient of the fluid, S T is the viscous dissipation term;

[0026] The component transport equations include:

[0027] The multi-component transport equations involving velocity field and temperature field are selected as follows:

[0028]

[0029] Among them, c f is the volume concentration of component f, D f is the diffusion coefficient of component f;

[0030] The standard k-ε turbulence model includes:

[0031] In the selection of multi-index analysis, the air supply of the mushroom room is regarded as an incompressible fluid, and the standard k-ε turbulence two-equation model is selected:

[0032]

[0033] Among them, C μ =0.09, C1ε =1.44, C 2ε =1.92 are both turbulence constants, σ k =1.0,σ ε =1.3 are all turbulent Prandtl numbers, and the custom source term S k , S ε Set to 0.

[0034] Preferably, in S3, the iterative operation includes taking temperature and air velocity as convergence targets; during the iterative operation, the residual values ​​of wind speed and temperature in each direction of the space are stabilized within 10 -4 The convergence condition is considered to be met.

[0035] Preferably, in said S3, the method for obtaining the temporal and spatial distribution law of multiple indicators of the mushroom house is: by establishing longitudinal and transverse sections, the wind speed vector diagram and temperature distribution cloud diagram inside the edible mushroom house are obtained, and the temporal and spatial distribution law of each indicator of the edible mushroom house is intuitively fed back.

[0036] Compared with the prior art, the present invention has achieved the following technical effects:

[0037] The present invention can provide effective suggestions and feedback for improving the ventilation structure configuration of the edible mushroom house and optimizing the ventilation system, thereby providing a good growth environment for the mushrooms and ensuring the high efficiency of production. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a three-dimensional model of a CFD-based simulation analysis method for ventilation effect and airflow distribution in an edible mushroom house according to an embodiment of the present invention;

[0039] Figure 2 A velocity field distribution diagram of a CFD-based simulation analysis method for ventilation effect and airflow distribution of an edible mushroom house according to an embodiment of the present invention;

[0040] Figure 3 A schematic diagram of temperature field distribution of a CFD-based simulation analysis method for ventilation effect and airflow distribution in a mushroom house according to an embodiment of the present invention.

[0041] Figure 4 This is a diagram of average wind speed and average temperature of each floor of a mushroom house according to a CFD-based simulation analysis method for ventilation effect and airflow distribution of an edible mushroom house described in an embodiment of the present invention.

[0042] Figure 5 A comparative analysis diagram of wind speed and temperature measurement results and simulation results of a CFD-based edible mushroom house ventilation effect and airflow distribution simulation analysis method according to an embodiment of the present invention;

[0043] Among them, Figure a (x = 18.3m, y = 1.725m) and Figure c (x = 6.3m, y = 1.725m) show the change of wind speed with different heights;

[0044] Figure b (x = 18.3m, y = 1.725m) and Figure d (x = 6.3m, y = 1.725m) show the temperature changes with different altitudes;

[0045] Figure 6 A schematic diagram of velocity field distribution after removing the baffle above the aisle in a CFD-based simulation analysis method for ventilation effect and airflow distribution of an edible mushroom house according to an embodiment of the present invention;

[0046] Figure 7 This is a diagram of the average wind speed and average temperature of each floor in a mushroom house after adding ventilation holes according to a CFD-based simulation analysis method for ventilation effect and airflow distribution in an edible mushroom house described in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Example 1

[0049] The present invention discloses a CFD-based edible mushroom house environment control technology method, comprising the following steps:

[0050] S1: Conduct three-dimensional modeling of the edible mushroom house and establish a CFD flow field simulation model.

[0051] S2: According to the on-site test data of the edible mushroom house, the boundary conditions of the mushroom house are pre-processed and set, and multiple indicators of the mushroom house are simulated and calculated.

[0052] S3: By setting up planes at different heights and spatial orientations, the distribution patterns of multiple indicators of the mushroom house in time and space are obtained.

[0053] S4: Conduct ventilation effect analysis under common summer operating conditions to determine the location range of areas where parameters do not meet the standards.

[0054] like Figure 1As shown in the figure, the geometric dimensions of the mushroom house are 18.6m in length, 6.5m in width, and 8m in height. The air inlet pipe is arranged with 12 40mm air supply holes, and the exhaust pipe is arranged with 18 40mm exhaust holes. There are 4 rows of cultivation racks in the mushroom house, and each layer has 10 layers of cultivation racks. The interval between the upper and lower layers is about 50cm, and the interval between the left and right layers is about 80cm. The interval between the two middle rows is 30cm. The Cartesian coordinate system is used as the global coordinate system, and the height direction is the positive direction of the z-axis. Blender is used to establish a three-dimensional model of the mushroom house.

[0055] Specifically, in the process of model establishment, the model needs to be simplified to a certain extent to reduce the complexity of the calculation, ignore the wall thickness of the mushroom house, simplify some rounded corners in the geometric features of the mushroom house, consider the ventilation performance inside the mushroom house; ignore the cultivation racks, lighting equipment, staff, and mechanical parts.

[0056] The grid division plate provided by the open source OpenFOAM was used to divide the overall mushroom house model into grids according to the principle of local to global. The air supply duct, exhaust duct and the walls of the mushroom house were meshed separately. The grid subdivision level was set to 0-4 considering the computer performance and calculation accuracy. For some areas in the mushroom house with large flow field changes, grid encryption was focused on, and finally a total of 23,965,946 grids were obtained.

[0057] The pre-processing setting of the mushroom house model is internal flow field analysis; the effect of the gravity field needs to be considered when analyzing the humidity field, and the acceleration in the vertical direction of the three-dimensional model is calibrated to be "-9.81m / s 2 ", the acceleration in other directions is 0m / s 2 ; The wall condition of the whole mushroom house is set as "constant wall temperature", ignoring the wall roughness, and the wall temperature is stable at 20.2℃; the cooling source of the air cooler is set to 41955.08J / (m 3 ·s), the air cooler / turbulent fan and the humidifier are defined as momentum sources, with speeds of 11.11m / s and 2.3148m / s respectively.

[0058] The air outlet is further set to the pressureInletOutletVelocity boundary condition; the p_rgh pressure boundary condition is set to toTalPressure, and the value is set to 725pa; at the same time, the thermodynamic parameters are set according to the measured temperature at each air outlet, and the temperature value of each measuring point is also used as the reference temperature.

[0059] Set the temperature and air velocity as the convergence target. During the iterative calculation, the velocity residual value in each direction of the space is stable at 10 -4 The level is considered to have reached the convergence condition.

[0060] When selecting a mathematical model for a mushroom house, it is important to consider air as a conventional incompressible fluid, that is, the changes in the thermal conductivity, specific heat and other parameters of the medium with time and space are ignored. The control equations include the continuity equation, momentum equation, energy equation, component transport equation, and standard k-ε turbulence model.

[0061] The continuity equation includes:

[0062]

[0063] Among them, u is the component of velocity in the x direction, v is the component of velocity in the y direction, and w is the component of velocity in the z direction;

[0064] The momentum equation includes:

[0065]

[0066] Among them, μ eff is the effective viscosity, T is the air temperature, T ref is the air reference temperature, P is the static pressure, ρ is the air density, g is the gravitational acceleration, and β is the air thermal expansion coefficient;

[0067] The energy equation includes:

[0068]

[0069] Where T is the air temperature, k is the heat transfer coefficient of the fluid, S T is the viscous dissipation term;

[0070] The component transport equations include:

[0071] The multi-component transport equations involving velocity field and temperature field are selected as follows:

[0072]

[0073] Among them, c f is the volume concentration of component f, D f is the diffusion coefficient of component f;

[0074] The standard k-ε turbulence model includes:

[0075] In the selection of multi-index analysis, the air supply of the mushroom room is regarded as an incompressible fluid, and the standard k-ε turbulence two-equation model is selected:

[0076]

[0077] Among them, C μ =0.09, C 1ε =1.44, C 2ε=1.92 are both turbulence constants, σ k =1.0,σ ε =1.3 are all turbulent Prandtl numbers, and the custom source term S k , S ε Set to 0.

[0078] The results of the iterative calculation of this working condition are post-processed and analyzed. By establishing longitudinal and transverse sections, the wind speed vector diagram and temperature distribution cloud diagram of the mushroom house are obtained, which intuitively feedback the temporal and spatial distribution laws of various indicators of the mushroom house, thereby judging the quality of the ventilation effect under the current working condition, and providing effective support for the subsequent optimization of the ventilation system and improvement of the air supply speed.

[0079] like Figure 2 As shown in the figure, the entire mushroom room can be divided into two areas by the baffle at the top of the mushroom. The wind speed above the baffle is generally higher and the temperature is lower, while the wind speed below the baffle is lower and the temperature is higher. After entering the room, the fresh hot air in the mushroom room is cooled by the air cooler and given a high initial velocity, forming a jet. After being blocked by the baffle at the top of the mushroom, it cannot directly enter the lower mushroom growth area, and at the same time avoids the large area of ​​high wind speed in the mushroom growth area. Most of these airflows fall from the gap between the baffle and the surrounding walls and are sucked away by the air outlet duct.

[0080] like Figure 3 As shown, it is a schematic diagram of temperature field distribution of the ventilation effect and airflow distribution simulation analysis method of the edible mushroom house based on CFD of the present invention.

[0081] like Figure 4 As shown in the figure, the average wind speed and temperature distribution in the space of each layer of mushroom house are shown. The average wind speed of each layer of mushrooms is less than 0.3m / s, and the average temperature is less than 18.5℃. As can be seen from the figure, there is a strong correlation between temperature and wind speed. The wind speed is higher in the lowest layer. It can be seen from the figure that it is affected by the air intake at the air outlet. The downward airflow near the wall ventilates the upper area of ​​this layer of mushrooms, driving the air flow. The average wind speed of the mushroom airflow in the next five consecutive layers has almost no change. It can also be seen from the figure that part of the air flow in this area still flows through the mushroom growth area near the wall, but the flow area is quite limited. The average flow rate of the next four layers of mushrooms is also increasing with the increase in height. It can be seen from the figure that this change is not only affected by the outlet wall, but also by the inlet wall. On the inlet wall, especially in the gap between the two baffles in the middle of the mushroom house, a lot of air flow leaks and flows through the mushroom growth surface.

[0082] Since it is necessary to obtain the actual data of the on-site mushroom room environmental parameters to verify the simulation results, the specific instrument parameters used are shown in the following table:

[0083] Table 1: Field test equipment table

[0084]

[0085] like Figure 5 As shown, Figure a (x=18.3m, y=1.725m) and Figure c (x=6.3m, y=1.725m) represent the changes of wind speed with different heights; Figure b (x=18.3m, y=1.725m) and Figure d (x=6.3m, y=1.725m) represent the changes of temperature with different heights. The wind speed simulation data is very close to the measured wind speed, both within the measurement range. From 1.3-4.8m, the measured wind speed trend and the simulated wind speed trend both show a trend of first rising and then falling, but the simulated value is larger than the measured average value, with a difference of 0.1-0.3m / s. The possible reasons are: 1. There is no suitable fan performance curve for the air cooler, and the ventilation volume is used as the standard setting, which may not be in line with reality, resulting in deviations between the simulation results and the actual results; 2. Friction on the wall is not considered, which may cause the simulation results to be larger; 3. The distance from the wall here is relatively close, with only 10 grids between the wall, which may be affected by the wall treatment, resulting in deviations from the actual results. It can be seen from Figures b and d that the temperature simulation results can be more accurately consistent with the measurement results, and the simulation values ​​at the lower position of Figure d can also be well consistent with the experimental results, but starting from 2.8m, a large vortex is formed in the upper area of ​​this position, and the cold air driven by the air cooler above is blocked by the middle baffle, and a small part of the gas falls down. This phenomenon was not found on the other side of the middle baffle. Overall, this phenomenon only affected the three layers above the mushrooms near the aisle area and did not affect the simulation results.

[0086] like Figure 6 As shown, when the baffle above the aisle is removed, Figure 2 By comparison, it was found that a downward airflow was formed in the middle of the aisle, which participated in the air circulation of the 7th, 8th and 9th floors, and effectively supplemented the air circulation of the mushrooms on the air intake side. When the baffles were removed, the average wind speed of each floor increased to a certain extent compared with the previous one, among which the 7th floor increased by 0.064m / s, about 26%, which was the largest increase. In terms of average temperature, there was no significant difference between the two, but in terms of unevenness, the removal of the baffles in the middle reduced the uniformity of temperature distribution compared with the non-removal of the baffles, and the overall reduction was 11.3%. Combined with field practice, this study considered that wind speeds greater than 0.5m / s may affect the growth performance of mushrooms, and wind speed areas below 0.1m / s were considered to form ventilation dead corners. However, removing the baffles also brought another part of the impact. When the baffles were removed, the area with wind speeds greater than 0.5m / s accounted for 6.99% of the total area, compared with 4.66% before; when the baffles were removed, the area with wind speeds less than 0.1m / s accounted for 9.95% of the total area, compared with 16.24% before. While reducing ventilation death, it also increases the area with excessive wind speed.

[0087] like Figure 7 As shown in the figure, after adding the vents, the air flow rate increased to 0.719 kg / s, which is 44.14% higher than before optimization. The air velocity in the mushroom growth area increased very little, and the overall average wind speed increased by 3.5%. The increase in flow caused by the increase in the outlets led to more high wind speed areas and higher wind speeds in the top layer, but from the 8th layer onwards, the speed distribution was almost the same as before optimization. However, in terms of distribution uniformity, it can be seen that the speed uniformity did not change much overall, but there were huge differences between the layers, and the temperature uniformity was very different, with an overall decrease of 16.4%. This may be because the temperature is closer to the set temperature of the mushroom surface at this time, and the difference between the airflow and the heat source temperature is reduced, resulting in a more uniform heat transfer effect. The area with a wind speed greater than 0.5 m / s accounts for 7.98% of the total area, an increase of 3.32% compared to before optimization; the area with a wind speed less than 0.1 m / s accounts for 11.63% of the total area, a decrease of 4.60% compared to before optimization. When the ventilation volume increases, more high wind speed areas appear. In terms of ventilation effect, adding vents did not change the low air circulation on the surface of the indoor mushroom growing area. However, the increase in air flow resulted in more energy required for cooling, which was obviously uneconomical.

[0088] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A CFD-based edible mushroom house environment control technology method, characterized in that: The steps include: S1: Conduct 3D modeling of the edible mushroom house and establish a CFD flow field simulation model; S2: According to the test data of the environmental parameters of the edible mushroom house, the boundary conditions of the mushroom house are pre-processed and set, and multiple indicators of the mushroom house are simulated and calculated; S3: By setting plane diagrams of different heights and spatial orientations, performing post-processing analysis of the results through iterative calculations, the distribution patterns of multiple indicators of the mushroom house in time and space are obtained; S4: Conduct ventilation effect analysis under common summer operating conditions to determine the location range of areas where parameters do not meet the standards.

2. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: It also includes using the open source software Blender to create a simplified model and using the grid division plate that comes with the open source OpenFOAM to grid the overall mushroom house model according to the principle of local to overall; gridding the air supply duct, exhaust duct and each wall of the mushroom house body separately; setting the grid refinement level to 0-4 levels by comprehensively considering the computer's performance and calculation accuracy; focusing on grid encryption processing for areas where the air flow field inside the mushroom house changes greatly, and obtaining a total of 23,965,946 grids.

3. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: In S1, the method for three-dimensional modeling of the edible mushroom house is: simplifying the three-dimensional modeling, ignoring the wall thickness of the mushroom house, simplifying some rounded corners in the geometric features of the mushroom house, considering the ventilation performance inside the mushroom house; ignoring the cultivation racks, lighting equipment, staff, and mechanical parts.

4. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: In S2, the distribution of ventilation holes and environmental parameter measurement points of the mushroom house shows that 18 points are arranged indoors, of which 5 points are arranged under the first ventilation hole of the air inlet pipe, 5 points are arranged under the second ventilation hole, 4 points are arranged in the middle, 6 layers are missing, these points are on the 2nd, 4th, 6th, 8th, and 10th layers, respectively at the positions of 0.8, 1.8, 2.8, 3.8, and 4.8; these are all placed in the column of 14 points against the wall; there are also 4 points arranged in the middle column of mushrooms, 6 layers are missing, placed in the middle column of mushrooms, and 4 points are about 20-30cm away from the passage.

5. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: In S2, the boundary condition pre-processing setting method of the mushroom house is: setting the edible mushroom house model for internal flow field analysis; considering the effect of the gravity field when analyzing the humidity field, calibrating the acceleration in the vertical direction of the three-dimensional model to -9.81m / s 2 , the acceleration in other directions is 0m / s 2 ; For the whole edible mushroom house wall condition, the wall temperature is set to a constant temperature, ignoring the wall roughness, and the wall temperature is stable at 20.2℃; the cooling source of the air cooler is set to 41955.08J / (m 3 ·s), the air cooler / turbulent fan and humidifier are defined as momentum sources, with speeds of 11.11m / s and 2.3148m / s respectively; the air outlet is set to the pressureInletOutletVelocity boundary condition; the p_rg pressure boundary condition is set to toTalPressure, and the value is set to 725pa; at the same time, the thermodynamic parameters and humidity parameters are set according to the measured temperature at each air outlet, and the temperature value of each measuring point is also used as the reference temperature; The flow field fluid is air, and the ventilation structure is optimized and adjusted based on the comparison between the temperature field and wind speed field obtained by simulation and the results measured on site.

6. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: In S2, the multiple indicators of the mushroom house include: wind speed and temperature.

7. The CFD-based edible mushroom house environment control technology method according to claim 1 is characterized in that: In S2, the simulation calculation of multiple indicators of the mushroom house is carried out through a group of control equations, specifically including a continuity equation, a momentum equation, an energy equation, a component transport equation and a standard k-ε turbulence model.

8. The CFD-based edible mushroom house environment control technology method according to claim 7 is characterized in that: The continuity equation includes: Among them, u is the component of velocity in the x direction, v is the component of velocity in the y direction, and w is the component of velocity in the z direction; The momentum equation includes: Among them, μ eff is the effective viscosity, T is the air temperature, T ref is the air reference temperature, P is the static pressure, ρ is the air density, g is the gravitational acceleration, and β is the air thermal expansion coefficient; The energy equation includes: Where T is the air temperature, k is the heat transfer coefficient of the fluid, S T is the viscous dissipation term; The component transport equations include: The multi-component transport equations involving velocity field and temperature field are selected as follows: Among them, c f is the volume concentration of component f, D f is the diffusion coefficient of component f; The standard k-ε turbulence model includes: In the selection of multi-index analysis, the air supply of the mushroom room is regarded as an incompressible fluid, and the standard k-ε turbulence two-equation model is selected: Among them, C μ =0.09, C 1ε =1.44, C 2ε =1.92 are both turbulence constants, σ k =1.0,σ ε =1.3 are all turbulent Prandtl numbers, and the custom source term S k , S ε Set to 0.

9. The CFD-based edible mushroom house environment control technology method according to claim 1, characterized in that: In S3, the iterative operation includes taking temperature and air velocity as convergence targets; during the iterative operation, the residual values ​​of wind speed and temperature in each direction of the space are stabilized at 10 -4 The convergence condition is considered to be met.

10. The CFD-based edible mushroom house environment control technology method according to claim 1, characterized in that: In S3, the method for obtaining the temporal and spatial distribution laws of multiple indicators of the mushroom house is: by establishing longitudinal and transverse sections, the wind speed vector diagram and temperature distribution cloud diagram inside the edible mushroom house are obtained, and the temporal and spatial distribution laws of various indicators of the edible mushroom house are intuitively fed back.

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