CN114065522A - Wall heat flux determination method combined with software - Google Patents
Wall heat flux determination method combined with software Download PDFInfo
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- CN114065522A CN114065522A CN202111369842.0A CN202111369842A CN114065522A CN 114065522 A CN114065522 A CN 114065522A CN 202111369842 A CN202111369842 A CN 202111369842A CN 114065522 A CN114065522 A CN 114065522A
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- 230000004907 flux Effects 0.000 title claims abstract description 58
- 238000000034 method Methods 0.000 title claims abstract description 36
- 238000009413 insulation Methods 0.000 claims description 158
- 229920002635 polyurethane Polymers 0.000 claims description 27
- 239000004814 polyurethane Substances 0.000 claims description 27
- 239000000463 material Substances 0.000 claims description 23
- 238000004364 calculation method Methods 0.000 claims description 14
- 238000004088 simulation Methods 0.000 claims description 11
- 238000013461 design Methods 0.000 claims description 9
- 238000005520 cutting process Methods 0.000 claims description 4
- 230000001052 transient effect Effects 0.000 claims description 4
- 238000011160 research Methods 0.000 claims description 3
- 238000004422 calculation algorithm Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 claims description 2
- 238000003860 storage Methods 0.000 claims description 2
- 238000012546 transfer Methods 0.000 abstract description 13
- 239000012530 fluid Substances 0.000 description 11
- 238000005057 refrigeration Methods 0.000 description 5
- 239000002131 composite material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000009355 double cropping Methods 0.000 description 2
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- 230000001133 acceleration Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
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- 238000005457 optimization Methods 0.000 description 1
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- G06F30/00—Computer-aided design [CAD]
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- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
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Abstract
The invention relates to the field of heat transfer, in particular to a wall heat flux determination method combining software.
Description
Technical Field
The invention relates to the field of heat transfer, in particular to a wall surface heat flux determination method combined with software.
Background
In cold chain transportation, a refrigerated container is a common low-temperature transportation device, and different low-temperature environments can be prepared to ensure that frozen and refrigerated foods are transported from manufacturers to consumers in a high-quality state. The outdoor heat can influence the low-temperature environment in the refrigerated container, and the wall surface of the refrigerated container is made of a material with strong heat insulation performance, so that the influence of the outdoor heat on the low-temperature environment in the refrigerated container can be effectively reduced. The wall surface of the conventional refrigerated container adopts a mode of stacking a plurality of layers of composite materials, the total heat transfer coefficient of the composite wall surface can be calculated through the heat transfer coefficients of different materials, and the heat insulation capability of the wall surface is judged according to the parameter. But this method is not applicable to walls with different materials in the same cross-section. The vacuum heat insulation plate is a material with strong heat insulation performance, the heat transfer coefficient is 0.002-0.008W/(m.K), but the size specification of the vacuum heat insulation plate is small, and the vacuum heat insulation plate is difficult to manufacture into some special sizes, so that a multi-plate splicing mode is adopted, and gaps are filled with polyurethane. The gap between the vacuum insulation panels can cause a heat bridge effect and influence the heat insulation capability, the conventional method for calculating the total heat transfer coefficient of the composite wall surface is not suitable for judging the heat insulation performance of the wall surface, and if a method capable of judging the heat insulation performance of the wall surface with different materials on the same section is provided, the method plays a positive role in optimizing the design of the wall surface of the refrigerated container.
Disclosure of Invention
The invention aims to provide a wall heat flux determining method combined with software, wherein the heat flux of a wall to be researched at different positions and different running moments is determined in a numerical simulation mode by combining with Workbench software, and the heat performance of different walls is determined by comparing the heat flux.
In order to achieve the above objects, one embodiment of the present invention provides a wall heat flux determining method in combination with software, including a refrigerated container case, a refrigerating unit, a front sidewall, a vacuum insulation panel, and polyurethane;
the front side wall surface has two forms, namely a first type front side wall surface form and a second type front side wall surface form;
the vacuum insulation panels comprise a first vacuum insulation panel, a second vacuum insulation panel, a third vacuum insulation panel, a fourth vacuum insulation panel, a fifth vacuum insulation panel, a sixth vacuum insulation panel, a seventh vacuum insulation panel, an eighth vacuum insulation panel, a ninth vacuum insulation panel, a tenth vacuum insulation panel, an eleventh vacuum insulation panel and a twelfth vacuum insulation panel;
the polyurethane comprises a first polyurethane and a second polyurethane;
the first vacuum insulation panel, the second vacuum insulation panel, the third vacuum insulation panel, the fourth vacuum insulation panel, the fifth vacuum insulation panel, the sixth vacuum insulation panel and the first polyurethane form a first type of front side wall surface form;
the seventh vacuum insulation panel, the eighth vacuum insulation panel, the ninth vacuum insulation panel, the tenth vacuum insulation panel, the eleventh vacuum insulation panel, the twelfth vacuum insulation panel and the second polyurethane form a second type of front side wall surface form;
the process of the wall heat flux determination method in combination with the software is as follows:
1) drawing a three-dimensional model of the refrigerated container, and outputting the finished three-dimensional model as an X _ T file;
2) importing an X _ T file into a Workbench, processing (cutting) the interference problem caused by overlapping of different materials on the wall surface in the refrigerated container model, and renaming the surfaces, bodies and the like which can be encountered in subsequent operations;
3) drawing the grids of the model through a Mesh function;
4) in a numerical simulation calculation interface, setting an equation, a material, a boundary condition, an algorithm, a file storage form and the like according to the operating condition requirement of a model, and performing simulation calculation;
5) after the calculation is finished, entering CFD-Post, setting the position of the cross section, and outputting the average heat flux of each cross section at different moments;
6) the obtained average heat flux is arranged and analyzed, the heat quantity transferred into the refrigerated container from the outside is equal to the product of the heat flux and the temperature difference between the two sides of the wall surface, and the smaller the average heat flux is, the less the heat quantity transferred into the refrigerated container from the outside is, and the better the heat insulation performance of the design of the wall surface is.
Preferably, the numerical simulation software used in the invention is Workbench, and the three-dimensional model drawing software used in the invention is SolidWorks.
Preferably, the interference problem due to the overlapping of different materials is handled in Workbench and not in SolidWorks.
Alternatively, the present invention is applicable to other wall forms having different materials in the same cross section, in addition to the first type of front wall form and the second type of front wall form.
Alternatively, the time step for transient calculation by numerical simulation can be 100s, 200s, 300s, etc., and is determined according to research requirements.
The invention provides a wall surface heat flux determining method combined with software, which is characterized in that the Workbench software is used for carrying out numerical simulation on the operation of a refrigerated container, so that the heat flux of the wall surface to be researched at different positions and different operation moments is determined, the heat performance of different wall surfaces can be determined by comparing the heat flux, and the design and optimization of the wall surface of the refrigerated container are actively played.
Drawings
Fig. 1 is a schematic perspective view of a refrigerated container incorporating the software wall heat flux determination method of the present invention, including 1-the refrigerated container housing, 2-the refrigeration unit, and 3-the front side wall.
Fig. 2 is a schematic front view of a first type of front sidewall profile of the wall heat flux determination method incorporating software according to the present invention, including 4.1-first vacuum insulation panel, 4.2-second vacuum insulation panel, 4.3-third vacuum insulation panel, 4.4-fourth vacuum insulation panel, 4.5-fifth vacuum insulation panel, 4.6-sixth vacuum insulation panel, and 5.1-first polyurethane.
Fig. 3 is a schematic front view of a second type of front sidewall form of the wall heat flux determination method incorporating software according to the present invention, including 4.7-seventh vacuum insulation panel, 4.8-eighth vacuum insulation panel, 4.9-ninth vacuum insulation panel, 4.10-tenth vacuum insulation panel, 4.11-eleventh vacuum insulation panel, 4.12-twelfth vacuum insulation panel, and 5.2-second polyurethane.
Fig. 4 is a diagram showing the variation of the average heat flux of each cross section when the operation time of the wall heat flux determination method of the present invention is 1800 s.
Fig. 5 is a schematic diagram showing the change of the average heat flux of each cross section when the operation time of the wall heat flux determination method of the present invention is 3600 s.
FIG. 6 is a graph showing the variation of the average heat flux at each time for a cross-section 20mm from the outer surface of the 3-front side wall using the wall heat flux determination method of the present invention in combination with software.
Detailed Description
The following describes embodiments of the present invention in detail with reference to the accompanying drawings.
The outer dimension of the refrigerated container shell 1 is 845 multiplied by 680 multiplied by 1325mm, the wall thickness is 40mm, the refrigerated container shell is composed of a vacuum insulation panel and a polyurethane material, the heat transfer coefficient of the vacuum insulation panel is equal to 0.006W/(m.K), the density is equal to 260kg/m for double-cropping, the specific heat is equal to 670J/(kg.K), the heat transfer coefficient of the polyurethane material is equal to 0.022W/(m.K), the density is equal to 50kg/m for double-cropping, the specific heat is equal to 589.6J/(kg.K), the refrigerated container shell 1 comprises a front side wall face 3, all wall faces except the front side wall face 3 are composed of a single polyurethane material, and the front side wall face 3 is a main research object.
As shown in fig. 1, a perspective view of a refrigerated container of the wall heat flux determination method in combination with software according to an embodiment of the present invention includes a refrigerated container housing 1, a refrigeration unit 2, and a front side wall 3; the refrigerating unit 2 has a size of 765 × 600 × 445mm, and is installed on the top of the inner side of the refrigerated container housing 1, with an air supply speed of 5m/s, an air supply temperature of 255.15K, and an outdoor temperature of 300.15K.
As shown in fig. 2, a front view of a first type of front sidewall form of a wall heat flux determining method of integrated software according to an embodiment of the present invention includes a first vacuum insulation panel 4.1, a second vacuum insulation panel 4.2, a third vacuum insulation panel 4.3, a fourth vacuum insulation panel 4.4, a fifth vacuum insulation panel 4.5, a sixth vacuum insulation panel 4.6, and a first polyurethane 5.1; the dimensions of the first vacuum insulation panel 4.1 and the second vacuum insulation panel 4.2 are 600 × 400 × 40 mm; the dimensions of the third vacuum insulation panel 4.3 are 600 x 300 x 40 mm; the dimensions of the fourth vacuum insulation panel 4.4, the fifth vacuum insulation panel 4.5 and the sixth vacuum insulation panel 4.6 are 600 × 200 × 40 mm; the first vacuum heat-insulating plate 4.1, the second vacuum heat-insulating plate 4.2, the third vacuum heat-insulating plate 4.3 and the fourth vacuum heat-insulating plate 4.4 are transversely arranged, the fifth vacuum heat-insulating plate 4.5 and the sixth vacuum heat-insulating plate 4.6 are vertically arranged, and the first vacuum heat-insulating plate 4.1, the second vacuum heat-insulating plate 4.2, the third vacuum heat-insulating plate 4.3, the fourth vacuum heat-insulating plate 4.4, the fifth vacuum heat-insulating plate 4.5 and the sixth vacuum heat-insulating plate 4.6 are tightly connected and tightly attached to the upper left corner of the front side wall surface 3; the first polyurethane 5.1 fills the portions of the front sidewall face 3 not covered by the first vacuum insulation panel 4.1, the second vacuum insulation panel 4.2, the third vacuum insulation panel 4.3, the fourth vacuum insulation panel 4.4, the fifth vacuum insulation panel 4.5, and the sixth vacuum insulation panel 4.6.
As shown in fig. 3, a front view of a second type of front sidewall form of the wall heat flux determining method of integrated software according to an embodiment of the present invention includes a seventh vacuum insulation panel 4.7, an eighth vacuum insulation panel 4.8, a ninth vacuum insulation panel 4.9, a tenth vacuum insulation panel 4.10, an eleventh vacuum insulation panel 4.11, a twelfth vacuum insulation panel 4.12, and a second polyurethane 5.2; the dimensions of the seventh vacuum insulation panel 4.7 and the eighth vacuum insulation panel 4.8 are 600 × 400 × 40 mm; the ninth vacuum insulation panel 4.9 has dimensions of 600 x 300 x 40 mm; the tenth 4.10, eleventh 4.11 and twelfth 4.12 vacuum insulation panels have dimensions of 600 x 200 x 40 mm; the seventh vacuum insulation panel 4.7, the eighth vacuum insulation panel 4.8, the ninth vacuum insulation panel 4.9 and the tenth vacuum insulation panel 4.10 are transversely arranged, the eleventh vacuum insulation panel 4.11 and the twelfth vacuum insulation panel 4.12 are vertically arranged, the seventh vacuum insulation panel 4.7, the eighth vacuum insulation panel 4.8, the ninth vacuum insulation panel 4.9, the tenth vacuum insulation panel 4.10, the eleventh vacuum insulation panel 4.11 and the twelfth vacuum insulation panel 4.12 are tightly connected, the distance from the left side and the right side of the front side wall surface 3 is 22.5mm, and the distance from the upper side and the lower side of the front side wall surface 3 is 12.5 mm; the second polyurethane 5.2 fills the portions of the front sidewall face 3 not covered by the seventh vacuum insulation panel 4.7, the eighth vacuum insulation panel 4.8, the ninth vacuum insulation panel 4.9, the tenth vacuum insulation panel 4.10, the eleventh vacuum insulation panel 4.11 and the twelfth vacuum insulation panel 4.12.
The process of the wall heat flux determination method in combination with the software is as follows:
1) drawing each part of the refrigerated container by drawing, cutting and other drawing commands by using Solidworks2014, combining the finished parts according to the drawing commands shown in the figures 1, 2 and 3 to form a complete refrigerated container model, respectively using the refrigerated container in the first type of front side wall surface form and the refrigerated container in the second type of front side wall surface form as two three-dimensional models, and storing the two three-dimensional models in an X _ T file form;
2) opening Workbench2014, selecting a Fluid Flow in a Toolbox column, dragging the selected Fluid Flow to the right panel, and establishing a Fluid Flow working module; right-clicking Geometry on a module of the Fluid Flow (Fluent), importing an X _ T file of the refrigerated container applying the first type of front side wall surface form into software, and opening a Design Modler; clicking the Generation to display the drawn three-dimensional model; clicking Tools in a menu bar of Design Modler, selecting a Fill option in a drop-down box, modifying the attribute in the Extraction Type into By Caps, clicking Generator, and creating a fluid domain (the fluid domain is the flowing area of the air in the refrigerated container); clicking the refrigerating unit 2 in the left menu bar by a right key, clicking the supress Body, and hiding the refrigerating unit 2; selecting the surface of the fluid domain corresponding to the air supply outlet of the refrigerating unit 2, renaming the surface to be Inlet, and clicking the Generator; selecting the surface of a fluid domain corresponding to the air return opening of the refrigerating unit 2, renaming the surface to be Outlet, and clicking the Generator; clicking Create in a menu bar of a Design Modler, selecting a Boolean option in a pull-down frame, adjusting the Operation form to be Substract, selecting a refrigerated container shell 1 from Target tires, selecting a first vacuum insulation panel 4.1, a second vacuum insulation panel 4.2, a third vacuum insulation panel 4.3, a fourth vacuum insulation panel 4.4, a fifth vacuum insulation panel 4.5 and a sixth vacuum insulation panel 4.6 from Tool tires, selecting to store a cut figure, clicking Generate, cutting the first vacuum insulation panel 4.1, the second vacuum insulation panel 4.2, the third vacuum insulation panel 4.3, the fourth vacuum insulation panel 4.4, the fifth vacuum insulation panel 4.5 and the sixth vacuum insulation panel 4.6 from a front side wall surface 3 to obtain a first polyurethane 5.1, selecting the first vacuum insulation panel 4.1, the second vacuum insulation panel 4.2, the third vacuum insulation panel 4.3, the fourth vacuum insulation panel 4.4, the fifth vacuum insulation panel 4.5 and the sixth vacuum insulation panel 4.6, and completely preserving the refrigerated container shell 4.6, clicking a right button, clicking From New Part, and connecting different wall materials to ensure normal heat transfer;
3) exiting from the interface of Design Modler, double-clicking the Mesh part in the Fluid Flow (Fluent) by a left key, and entering a grid drawing interface; clicking the Mesh of the left toolbar by a right key, clicking the Method in Insert, selecting all parts of the three-dimensional model of the refrigerated container, selecting Tetrahedrons in the drawing mode of the grid, clicking the Mesh of the left toolbar by the right key again, and clicking the Generator Mesh; right-clicking the Mesh of the left toolbar, clicking Sizing in Insert, reselecting all parts of the three-dimensional model of the refrigerated container, adjusting the size of a single grid to be 20mm, finally right-clicking the Mesh of the left toolbar, selecting Update, adjusting the size of the grid, and uploading to software;
4) exiting from the interface drawn by the grid, double-clicking Solution of a Fluid Flow (Fluent) module by a left key, and entering a numerical simulation calculation interface; clicking General, changing the options under the Time into Transient, namely selecting Transient calculation, selecting Pressure-Based by Type, selecting Absolute by Velocity Formulation, hooking on the Gravity, and inputting the Gravity acceleration of 9.81m/s2I.e. input y = -9.81 m/s2(ii) a Clicking Models, clicking Energy, hooking on Energy Equipment, clicking Viscous Models, selecting a k-epsilon model, and adjusting to be in a readable form; clicking Materials, changing air in the Fluid into compressible-ideal-gas, and setting a wall material in the Solid according to the density, specific heat capacity and heat transfer coefficient of the vacuum insulation plate and the polyurethane material; the left click on the Cell Zone Conditions in the left menu bar is carried out by a left key, and the first vacuum insulation panel 4.1, the second vacuum insulation panel 4.2, the third vacuum insulation panel 4.3, the fourth vacuum insulation panel 4.4 and the third vacuum insulation panel are arranged according to the wall material properties of the arranged vacuum insulation panels and the polyurethane material,Properties of a fifth vacuum insulation panel 4.5, a sixth vacuum insulation panel 4.6 and a first polyurethane 5.1; the left key double clicks the Boundary Conditions in the left menu bar, clicks the Inlet in the Task Page, sets the Velocity Magnitude to 5m/s, sets the Temperature to 255.15K, changes the Outlet to the outflow Boundary condition, selects the first vacuum insulation panel 4.1, the second vacuum insulation panel 4.2, the third vacuum insulation panel 4.3, the fourth vacuum insulation panel 4.4, the fifth vacuum insulation panel 4.5, the sixth vacuum insulation panel 4.6 and the first polyurethane 5.1, selects the Temperature in the heat transfer mode, and sets the outdoor Temperature to 300.15K; clicking on the Methods in the left menu bar, setting Scheme to SIMPLE, Gradient to Green-Gauss Cell Based, and Pressure to PRESTO! Setting Momentum as First Order Upwind, setting Turbule Kinteric Energy as First Order Upwind, setting Turbule Dissipation Rate as First Order Upwind, and setting Energy as First Order Upwind; clicking Autosave in the Calculation Activities, and setting to save the file for 1 time when 1 time step is calculated; clicking Initialization, and initializing a model; clicking Run calibration, setting the Time Step Size to be 100, and setting the Number of Time Steps to be 36, namely calculating the heat transfer change of the refrigerated container shell 1 after the refrigerated container runs for 3600s, particularly the heat transfer change of the front side wall surface 3; clicking the Calculation to calculate;
5) after the calculation of numerical simulation is completed, exiting a calculation interface of the numerical simulation, double clicking Results by a left key, entering CFD-Post, clicking Point/Plane in Location, setting 3 sections, wherein the distances between the 3 sections and the front side wall surface 3 are respectively equal to 10, 20 and 30mm, and outputting the average heat fluxes of the 3 sections at different moments through Calculators;
6) arranging the average heat flux of the 3 sections of the refrigerated container obtained by applying the first type of front side wall surface at different moments, and drawing a chart;
7) the above operation is repeated for a three-dimensional model of the refrigerated container using the second type of front side wall surface form and a chart is drawn.
As shown in fig. 4, an embodiment of the present invention provides a graph of the average heat flux of each section when the operation time of the wall heat flux determination method in combination with software is 1800 s.
As shown in fig. 5, an embodiment of the present invention provides a graph of the average heat flux of each section when the operation time of the wall heat flux determination method with software is 3600 s.
As shown in fig. 6, an embodiment of the present invention provides a graph of the average heat flux at each time point for a cross section 20mm away from the outer surface of the front side wall 3 in the wall heat flux determination method in combination with software.
When the refrigeration unit 2 has been operating for 1800s, the average heat flux over the front side wall 3 using the first type of front side wall profile is higher than the average heat flux over the front side wall 3 using the second type of front side wall profile over the same cross section; when the refrigeration unit 2 has been operated for 3600s, the average heat flux over the front side wall 3 utilizing the first type of front side wall form is higher than the average heat flux over the front side wall 3 utilizing the second type of front side wall form over the same cross section.
As shown in fig. 4 and 5, the average heat flux curves show linear or approximately linear variation, so that the average heat flux of the section having a distance of 20mm from the outer surface of the front side wall 3 is selected for analysis; as shown in fig. 6, as the operating time increases, the average heat flux of the cross section of 20mm from the outer surface of the front side wall face 3 on the front side wall face 3 using the first type of front side wall face and the front side wall face 3 using the second type of front side wall face increases, and the former is larger than the latter at any time.
Since the outdoor temperature and the low temperature environment in the refrigerated container are constant, and the heat quantity transmitted into the refrigerated container outdoors is equal to the product of the average heat flux and the temperature difference between the inner and outer wall surfaces, the heat insulation performance of the front side wall surface 3 using the second type of front side wall surface form is better.
When the present invention is used to determine heat flux, parameters such as outdoor temperature and temperature inside the refrigeration container need to be determined, and the present invention cannot be used to determine heat flux only by knowing the material and combination of the front wall surface 3.
The above embodiments are merely illustrative of the design principles and applications of the present invention, and do not limit the present invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (5)
1. The wall surface heat flux determination method combined with software is characterized in that:
the method for determining the wall surface heat flux by combining software comprises a refrigerated container shell (1), a refrigerating unit (2), a front side wall surface (3), a vacuum insulation panel and polyurethane;
the front side wall (3) has two forms, namely a first type front side wall form and a second type front side wall form;
the vacuum insulation panel comprises a first vacuum insulation panel (4.1), a second vacuum insulation panel (4.2), a third vacuum insulation panel (4.3), a fourth vacuum insulation panel (4.4), a fifth vacuum insulation panel (4.5), a sixth vacuum insulation panel (4.6), a seventh vacuum insulation panel (4.7), an eighth vacuum insulation panel (4.8), a ninth vacuum insulation panel (4.9), a tenth vacuum insulation panel (4.10), an eleventh vacuum insulation panel (4.11) and a twelfth vacuum insulation panel (4.12);
the polyurethane comprises a first polyurethane (5.1) and a second polyurethane (5.2);
the first vacuum insulation panel (4.1), the second vacuum insulation panel (4.2), the third vacuum insulation panel (4.3), the fourth vacuum insulation panel (4.4), the fifth vacuum insulation panel (4.5), the sixth vacuum insulation panel (4.6) and the first polyurethane (5.1) form a first type of front side wall surface form;
the seventh vacuum insulation panel (4.7), the eighth vacuum insulation panel (4.8), the ninth vacuum insulation panel (4.9), the tenth vacuum insulation panel (4.10), the eleventh vacuum insulation panel (4.11), the twelfth vacuum insulation panel (4.12) and the second polyurethane (5.2) form a second type front side wall surface form;
the process of the wall heat flux determination method in combination with the software is as follows:
1) drawing a three-dimensional model of the refrigerated container, and outputting the finished three-dimensional model as an X _ T file;
2) importing an X _ T file into a Workbench, processing (cutting) the interference problem caused by overlapping of different materials on the wall surface in the refrigerated container model, and renaming the surfaces, bodies and the like which can be encountered in subsequent operations;
3) drawing the grids of the model through a Mesh function;
4) in a numerical simulation calculation interface, setting an equation, a material, a boundary condition, an algorithm, a file storage form and the like according to the operating condition requirement of a model, and performing simulation calculation;
5) after the calculation is finished, entering CFD-Post, setting the position of the cross section, and outputting the average heat flux of each cross section at different moments;
6) the obtained average heat flux is arranged and analyzed, the heat quantity transferred into the refrigerated container from the outside is equal to the product of the heat flux and the temperature difference between the two sides of the wall surface, and the smaller the average heat flux is, the less the heat quantity transferred into the refrigerated container from the outside is, and the better the heat insulation performance of the design of the wall surface is.
2. The software-integrated wall heat flux determination method of claim 1, wherein:
the numerical simulation software used in the invention is Workbench, and the three-dimensional model drawing software used in the invention is SolidWorks.
3. The software-integrated wall heat flux determination method of claim 1, wherein:
the interference problem due to the overlapping of different materials is dealt with in Workbench and not in SolidWorks.
4. The software-integrated wall heat flux determination method of claim 1, wherein:
in addition to the first type of leading edge profile and the second type of leading edge profile, the present invention is also applicable to other wall profiles having different materials in the same cross-section.
5. The software-integrated wall heat flux determination method of claim 1, wherein:
the time step for carrying out transient calculation by numerical simulation can be 100s, 200s, 300s and the like, and is determined according to research requirements.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111369842.0A CN114065522A (en) | 2021-11-18 | 2021-11-18 | Wall heat flux determination method combined with software |
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| CN202111369842.0A CN114065522A (en) | 2021-11-18 | 2021-11-18 | Wall heat flux determination method combined with software |
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| CN112580245A (en) * | 2021-01-06 | 2021-03-30 | 上海海洋大学 | Numerical simulation method for boiling simulation in smooth sleeve |
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