Method for designing rapid heating jig based on finite element simulation

Abstract

The invention discloses a method for designing a rapid heating jig based on finite element simulation. The method comprises the following steps that S10, 3D model simulation is conducted on a heating jig and a product model; s20, obtaining a thermal simulation analysis result, comparing the thermal simulation analysis result with a preset condition, judging whether the thermal simulation analysis result meets a heating requirement or not, if yes, S30, ending, and finishing the design; and if not, S40, modifying the heating jig model, and returning to S10. According to the method, simulation analysis and jig design are combined, and the heating jig meeting the requirements can be rapidly and accurately obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal analysis and relates to a method for designing a rapid heating fixture based on finite element simulation. Background Art

[0002] Whether the heating fixture design can meet the requirements of rapid heating of the product. The traditional method includes fixture mold opening, product assembly, actual temperature measurement, and finally whether the design is feasible. If it cannot meet the requirements of rapid heating of the product, the design needs to be modified and the above steps need to be repeated, which takes too long and the mold opening fee is expensive.

[0003] Finite element simulation can be used to perform solid heat transfer simulation analysis based on the three-dimensional model of the heating fixture and the product. The results can be used to determine whether the fixture design meets the requirements of rapid temperature rise of the product. This can reduce the cost of time and money and obtain more accurate temperature measurement results. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for designing a rapid heating fixture based on finite element simulation, comprising the following steps:

[0005] S10, performing 3D model simulation on the heating fixture and the product model;

[0006] S20, obtain the thermal simulation analysis results, compare them with the preset conditions, and determine whether they meet the temperature increase requirements. If yes, then S30, end and complete the design;

[0007] If no, then in S40, the heating fixture model is modified and the process returns to S10.

[0008] Preferably, the 3D model simulation in S10 adopts ANSYS's SCDM module or Unigraphics NX or Solidworks.

[0009] Preferably, the S10 comprises the following steps:

[0010] S11, importing the heating fixture and the product three-dimensional model into the 3D model simulation software, establishing an assembly relationship consistent with the actual working conditions, and simplifying the structure of the imported three-dimensional model;

[0011] S12, define the thermal physical parameters of the heating fixture and the product;

[0012] S13, defining the contact relationship between the heating fixture and the product and setting the thermal parameters between the contact objects;

[0013] S14, the simulation model is established, and the grids matching the heating fixture and the product are divided according to their shapes and sizes. The grid size of the temperature measurement area is smaller than that of other areas;

[0014] S15, define boundary conditions.

[0015] Preferably, the structural simplification in S11 includes removing chamfers and holes that are smaller than a set range.

[0016] Preferably, the thermophysical property parameters in S12 include density, thermal conductivity and specific heat capacity.

[0017] Preferably, the thermal parameter between the contact objects in S13 is contact thermal resistance.

[0018] Preferably, the boundary conditions in S15 include the initial temperature of the heating fixture, the initial temperature of the product, the ambient temperature and the heating time.

[0019] Preferably, the step S40 of modifying the heating fixture model includes changing the thermal conductivity of the heating fixture.

[0020] Preferably, the step S40 of modifying the heating jig model includes changing the contact area between the heating jig and the product.

[0021] Preferably, the step S40 of modifying the heating jig model includes changing the surface smoothness of the heating jig.

[0022] The beneficial effects of the present invention include at least:

[0023] 1. Greatly shorten the product assembly development cycle and save time;

[0024] 2. Reduce the number of mold opening times and save the cost of multiple mold openings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flowchart of the steps of the method for designing a rapid heating fixture based on finite element simulation of the present invention;

[0026] Figure 2 A structural diagram of a heating fixture that does not meet heating requirements according to a method for designing a fast heating fixture based on finite element simulation in a specific embodiment of the present invention;

[0027] Figure 3 A heating fixture and a product structure diagram that do not meet the heating requirements of a fast heating fixture design method based on finite element simulation according to a specific embodiment of the present invention;

[0028] Figure 4 This is a simulation diagram of the surface temperature distribution of the product after heating for 40 seconds that does not meet the heating requirements based on finite element simulation of the rapid heating fixture design method of the specific embodiment of the present invention;

[0029] Figure 5 It is a curve diagram of the lowest temperature point in the temperature measurement area that does not meet the heating requirement of the rapid heating fixture design method based on finite element simulation in a specific embodiment of the present invention;

[0030] Figure 6 It is a structural diagram of a heating fixture that meets the heating requirement after modification of S40 of the method for designing a fast heating fixture based on finite element simulation in a specific embodiment of the present invention;

[0031] Figure 7 A heating fixture and a product structure diagram that meet the heating requirements after modification of S40 of the method for designing a rapid heating fixture based on finite element simulation in a specific embodiment of the present invention;

[0032] Figure 8 This is a simulation diagram of the surface temperature distribution of the product after heating for 40 seconds, which is modified based on finite element simulation of S40 of the rapid heating fixture design method according to a specific embodiment of the present invention and meets the heating requirements;

[0033] Fig. 9 It is a curve diagram of the lowest temperature point in the temperature measurement area that meets the heating requirement after the S40 of the rapid heating fixture design method based on finite element simulation is modified according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0035] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below. Those skilled in the art can fully understand the present invention without the description of these details.

[0036] See also Figure 1 , is a flow chart of the overall steps of the present invention, comprising the following steps:

[0037] S10, performing 3D model simulation on the heating fixture and the product model;

[0038] S20, obtain the thermal simulation analysis results, compare them with the preset conditions, and determine whether they meet the temperature increase requirements. If yes, then S30, end and complete the design;

[0039] If no, then in S40, the heating fixture model is modified and the process returns to S10.

[0040] The 3D model simulation in S10 uses ANSYS's SCDM module, Unigraphics NX or Solidworks. Any simulation software that can complete the assembly relationship of the 3D model can be used.

[0041] S10 includes the following steps:

[0042] S11, importing the heating fixture and the product three-dimensional model into the 3D model simulation software, establishing an assembly relationship consistent with the actual working conditions, and simplifying the structure of the imported three-dimensional model;

[0043] S12, define the thermal physical parameters of the heating fixture and the product;

[0044] S13, defining the contact relationship between the heating fixture and the product and setting the thermal parameters between the contact objects;

[0045] S14, the simulation model is established, and the grids matching the heating fixture and the product are divided according to their shapes and sizes. The grid size of the temperature measurement area is smaller than that of other areas;

[0046] S15, define boundary conditions.

[0047] Structural simplification in S11 includes removing chamfers and holes that are smaller than a set range.

[0048] The thermophysical parameters in S12 include density, thermal conductivity and specific heat capacity.

[0049] The thermal parameter between the contact objects in S13 is the contact thermal resistance.

[0050] The temperature measurement area in S14 refers to the temperature of the product body. Generally, the temperature measurement area is located at the speaker mesh, lens hole, volume adjustment button and other places with glue.

[0051] The boundary conditions in S15 include the initial temperature of the heating fixture, the initial temperature of the product, the ambient temperature and the heating time.

[0052] S40 Modifying the heating fixture model includes changing the thermal conductivity of the heating fixture, generally replacing the heating fixture with a material having a high thermal conductivity.

[0053] It also includes changing the contact area and contact method between the heating fixture and the product. When two solids are in contact for heat transfer, the larger the contact area, the more channels there are for heat transfer, and the faster the heat transfer rate. The contact method will also affect the heat transfer rate. If there is a gap or air layer between the two solids (this is the reason for the existence of contact thermal resistance), the heat transfer rate will be hindered; and if the two solids are in close contact without a gap or air layer, the heat transfer rate will be relatively fast. We will focus on this influencing factor and generally change the contact area between the heating fixture and the product to control the temperature from being too high or too low.

[0054] It also includes adjusting the heat transfer temperature difference, which is the driving force of heat transfer. The greater the temperature difference, the faster the heat transfer. If the requirement for rapid heating is not met within the specified time, the temperature of the heating fixture will be increased.

[0055] It also includes adjusting external environmental factors such as temperature, humidity, wind speed, etc., which will also affect the solid heat transfer rate.

[0056] In a specific embodiment, the temperature increase requirement judgment condition in S20 is to keep warm for 40 seconds and the temperature reaches 75°C within 10 seconds. Figure 2-Figure 5 The heating fixture that does not meet the heating requirement and its corresponding contact structure diagram with the product, the surface temperature distribution diagram of the product after heating for 40 seconds, and the curve diagram of the lowest temperature point in the temperature measurement area are shown in S20. If the heating requirement is not met, the heating fixture model is modified as follows: Figure 6 In this embodiment, the contact area of ​​the heating fixture structure is modified, see Figure 6-Figure 9 The following are the heating fixtures that meet the heating requirements and their corresponding structure diagrams in contact with the product, the surface temperature distribution diagram of the product after heating for 40 seconds, and the curve diagram of the lowest temperature point in the temperature measurement area. Figure 7 The middle area 1 is Figure 6 The middle left area and area 2 are Figure 6 The middle right area, Fig. 9 The middle area 1 is Figure 8 The middle left area and area 2 are Figure 8 The middle right area. It can be seen that by only modifying the structure of the heating fixture so that the contact area between the heating fixture and the product is increased, the heating requirement can be met without changing the material of the heating fixture or adjusting the heat transfer temperature difference or changing the contact method between the heating fixture and the product. Through the simulation analysis of this application, the design efficiency and accuracy of the heating fixture are greatly improved.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for designing a rapid heating fixture based on finite element simulation, characterized in that: The following steps are involved: S10, performing 3D model simulation on the heating fixture and the product model; S20, obtain the thermal simulation analysis results, compare them with the preset conditions, and determine whether they meet the temperature increase requirements. If yes, then S30, end and complete the design; If no, then in S40, the heating fixture model is modified and the process returns to S10.

2. According to claim 1, a method for designing a rapid heating fixture based on finite element simulation is characterized in that: The 3D model simulation in S10 adopts the SCDM module of ANSYS or Unigraphics NX or Solidworks.

3. According to claim 1, a method for designing a rapid heating fixture based on finite element simulation is characterized in that: The S10 comprises the following steps: S11, importing the heating fixture and the product three-dimensional model into the 3D model simulation software, establishing an assembly relationship consistent with the actual working conditions, and simplifying the structure of the imported three-dimensional model; S12, define the thermal physical parameters of the heating fixture and the product; S13, defining the contact relationship between the heating fixture and the product and setting the thermal parameters between the contact objects; S14, the simulation model is established, and the grids matching the heating fixture and the product are divided according to their shapes and sizes. The grid size of the temperature measurement area is smaller than that of other areas; S15, define boundary conditions.

4. According to claim 3, a method for designing a rapid heating fixture based on finite element simulation is characterized in that: The structural simplification in S11 includes removing chamfers and holes that are smaller than a set range.

5. The method for designing a rapid heating fixture based on finite element simulation according to claim 3 is characterized in that: The thermophysical property parameters in S12 include density, thermal conductivity and specific heat capacity.

6. The method for designing a rapid heating fixture based on finite element simulation according to claim 3 is characterized in that: The thermal parameter between the contact objects in S13 is the contact thermal resistance.

7. The method for designing a rapid heating fixture based on finite element simulation according to claim 3 is characterized in that: The boundary conditions in S15 include the initial temperature of the heating fixture, the initial temperature of the product, the ambient temperature and the heating time.

8. The method for designing a rapid heating fixture based on finite element simulation according to claim 1, characterized in that: The step S40 of modifying the heating fixture model includes changing the thermal conductivity of the heating fixture.

9. The method for designing a rapid heating fixture based on finite element simulation according to claim 1, characterized in that: The step S40 of modifying the heating fixture model includes changing the contact area between the heating fixture and the product.

10. The method for designing a rapid heating fixture based on finite element simulation according to claim 1, characterized in that: The step S40 of modifying the heating jig model includes changing the surface smoothness of the heating jig.

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