CN111723472B - Heat exchanger structure optimization method based on hot melt gas-liquid two-phase heat exchange structure - Google Patents

Abstract

The invention relates to a heat exchanger structure optimization method based on a hot melt type gas-liquid two-phase heat exchange structure, which comprises the following steps of: s1: constructing a hot melt type gas-liquid two-phase heat exchange function based on a sine-cosine function according to a hot melt type gas-liquid two-phase heat exchange structure; s2: and carrying out three-dimensional modeling to construct a heat exchange unit body. S3: repeatedly executing the step S2, adjusting parameters, and obtaining an optimal unit body meeting the preset gas-liquid volume ratio condition; s4: obtaining a set unit consisting of preferred unit bodies through a fast iterative array; s5: repeatedly executing the step S4 to obtain a preferred set with optimal surface area and quality; s6: stress optimization is carried out; s7: performing 3D printing optimization; s8: and integrating the preferred assemblies to obtain the final heat exchanger structure. Compared with the prior art, the invention adopts a hot melt type gas-liquid two-phase heat exchange structure, breaks through the selection of the traditional design structure mode, and realizes double breakthroughs in heat transfer efficiency and weight.

Description

Heat exchanger structure optimization method based on hot melt gas-liquid two-phase heat exchange structure

technical field

The invention relates to the field of heat exchanger structures, in particular to a heat exchanger structure optimization method based on a hot melt type gas-liquid two-phase heat exchange structure.

Background technique

The traditional structure design of heat exchangers relies on the production process of subtractive manufacturing, which makes it difficult to produce more complex shapes, which limits the further improvement of the relevant heat exchange efficiency to a certain extent. Although the related design relies on reducing the cell spacing and increasing the corrugated plate to effectively increase the related contact area, it still cannot get rid of the fact that the heat transfer area is smaller than the material area. It is impossible to make full use of the material area, resulting in a certain waste.

At the same time, with the standardization and maturity of the plates, the constraints of the process also lead to the fact that the heat exchange efficiency of the heat exchanger cannot be improved qualitatively through the novel structural model.

As shown in Figure 1, the design of the heat exchanger achieves a relatively efficient heat dissipation structure through highly standardized accessory design (organic combination of fins, grid plates, baffles, etc.), and is easy to weld and assemble. Highly optimized industrially proven product. However, it cannot effectively meet the dual requirements of weight reduction and higher heat exchange efficiency.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a heat exchanger structure optimization method based on a hot melt gas-liquid two-phase heat exchange structure that can improve heat exchange efficiency and reduce weight in order to overcome the above-mentioned defects of the prior art.

The object of the present invention can be realized through the following technical solutions:

A heat exchanger structure optimization method based on a hot melt gas-liquid two-phase heat exchange structure, comprising the following steps:

S1: According to the hot-melt gas-liquid two-phase heat exchange structure, based on the sine and cosine functions, construct the hot-melt gas-liquid two-phase heat transfer function;

S2: carry out three-dimensional modeling of the hot melt type gas-liquid two-phase heat transfer function to construct a heat exchange unit body;

S3: Repeat step S2, and adjust the parameters of the heat exchange unit body in each cycle, adjust the internal structure of the heat exchange unit body, and change the gas-liquid volume ratio of the heat exchange unit body, until obtaining The heat exchange unit body that satisfies the preset gas-liquid volume ratio condition is regarded as the preferred unit body;

S4: Obtain a set unit composed of the preferred unit body by rapidly iterating the array;

S5: Repeat step S4, and calculate the surface area and mass of the aggregate unit in each cycle, until the aggregate unit with the best surface area and quality is obtained as the preferred aggregate;

S6: perform mechanical simulation on the preferred set, so as to perform stress optimization;

S7: 3D printing evaluation is performed on the optimal set after stress optimization, so as to perform 3D printing optimization;

S8: Integrate the optimized set after 3D printing to obtain a final heat exchanger structure that meets the preset task requirements.

Further, the expression of the hot melt type gas-liquid two-phase heat transfer function is:

XL=x-bCos[(x/2)^2]

YL=y-bCos[(y/2)^2]

ZL=z-bCos[(z/2)^2]

p1=ContourPlot3D[Cos[XL]Sin[YL]+

Con[YL]Sin[ZL]+Cos[ZL]Sin[XL]=0,

{x,-Pi,Pi},{y,-Pi,Pi},{z,-Pi,Pi}]

In the formula, p1 is the hot melt gas-liquid two-phase heat transfer function, ContourPlot3D[*] is the three-dimensional space transformation function, x is the x-axis coordinate value, y is the y-axis coordinate value, z is the z-axis coordinate value, and b is the variable parameter.

Further, in step S3, the parameter adjustment of the heat exchange unit body is specifically, the parameter adjustment of the heat exchange unit body is performed by adjusting the variable parameter b.

Further, in step S5, in step S5, the surface area and mass are optimal, and the evaluation is performed based on the larger the surface area and the smaller the mass.

Further, in step S6, the means of stress optimization includes increasing the wall thickness.

Further, in step S7, the means of 3D printing optimization includes adding welded walls.

Further, in step S2, based on the Mathematica modeling platform, three-dimensional modeling of the hot melt gas-liquid two-phase heat transfer function is performed.

Further, the step S4 is specifically as follows: importing the preferred unit body into the grasshopper parametric modeling platform, and obtaining an aggregate unit composed of the preferred unit body by rapidly iterating the array.

Further, in step S6, in the simsolid platform, a mechanical simulation is performed on the preferred set.

Further, in step S8, the optimized set of 3D printing is integrated through the rhino&grasshopper platform.

Compared with the prior art, the present invention has the following advantages:

(1) High coordination: Mathematica mathematical modeling method is used at the source in the process of the present invention, and then relying on the grasshopper parameterization platform, the overall scope is quickly unified through mathematical formulas, and the linkage process of rapid analysis and high-speed optimization of monomers is realized.

(2) Different design thinking: For the manufacturing method of the heat exchanger of the present invention, the design method of additive manufacturing is selected at the source. The manufacturing method is novel and different from the traditional subtractive manufacturing method, which makes the design result complex and efficient. Sex is manufacturable.

(3) Effectively improve heat exchange efficiency and material utilization rate: relying on the hot melt type gas-liquid two-phase heat exchange mechanism, the present invention effectively improves the heat transfer area and effectively reduces the overall weight, taking the embodiment of the present invention as an example , effectively reducing the weight by about 16% and increasing the contact area by 26%. At the same time, relying on the structure of hot melt gas-liquid two-phase heat exchange, the effective utilization rate of materials is increased to nearly 100%.

(4) Excellent structure: The heat exchange unit structure designed by the hot melt gas-liquid two-phase heat exchange structure has self-supporting ability and can adjust the gas-liquid ratio according to the parameters, and the surface tension is almost zero. Liquid barrier is small.

Description of drawings

Fig. 1 is the schematic diagram of a heat exchanger structure in the prior art;

Fig. 2 is the schematic flow chart of the heat exchanger structure optimization method of the present invention;

3 is a schematic structural diagram of a heat exchanger after structural filling is performed by a grasshopper parametric modeling platform in an embodiment of the present invention;

4 is a schematic diagram of the structure of a heat exchanger obtained by the method for optimizing the structure of a heat exchanger of the present invention in an embodiment of the present invention;

5 is a schematic structural diagram of a heat exchange unit body constructed by a hot melt type gas-liquid two-phase heat transfer function in an embodiment of the present invention;

6 is an internal cross-sectional view of a heat exchange core body of a heat exchanger structure in an embodiment of the present invention;

FIG. 7 is a schematic diagram of the internal working of the gas-liquid two-phase heat exchange core in the embodiment of the present invention.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and provides a detailed implementation manner and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

Example 1

As shown in FIG. 2 , this embodiment provides a method for optimizing the structure of a heat exchanger based on a hot melt gas-liquid two-phase heat exchange structure. The hot melt type gas-liquid two-phase heat exchange parameters are used as the main control to realize the heat dissipation efficiency and the weight reduction of the overall radiator, including the following steps:

S1: According to the hot-melt gas-liquid two-phase heat exchange structure, based on the sine and cosine functions, construct the hot-melt gas-liquid two-phase heat transfer function;

It is equivalent to analyzing the mathematical principle of heat transfer in the existing design, in-depth analysis of the gas-liquid two-phase composition structure contained in the existing heat transfer structure, and combining with the means of additive manufacturing, the basic hot-melt gas-liquid type is obtained. Two-phase heat transfer function construction strategy. Through the in-depth combination optimization of the sine and cosine functions, the basic control method of the hot melt gas-liquid two-phase heat transfer function is obtained.

In this step, relying on the combined improvement of the sine and cosine functions, the plane sine and cosine linear molecules are transformed into a three-dimensional structure through three-dimensional space transformation. Relying on the highly periodic and variable parameters of the function, a porous helical structure with variable linkage is realized. Type gas-liquid two-phase heat transfer functional structure", which can adapt to the constraints of various environments and different heat exchange combinations.

The expression of the hot melt gas-liquid two-phase heat transfer function is:

XL=x-bCos[(x/2)^2]

YL=y-bCos[(y/2)^2]

ZL=z-bCos[(z/2)^2]

p1=ContourPlot3D[Cos[XL]Sin[YL]+

Con[YL]Sin[ZL]+Cos[ZL]Sin[XL]=0,

{x,-Pi,Pi},{y,-Pi,Pi},{z,-Pi,Pi}]

In the formula, p1 is the hot melt gas-liquid two-phase heat transfer function, ContourPlot3D[*] is the three-dimensional space transformation function, x is the x-axis coordinate value, y is the y-axis coordinate value, z is the z-axis coordinate value, and b is the variable parameter. In this embodiment, the value of the variable parameter b is set to 1 at the initial moment.

Among them, XL, YL, ZL can realize the overall adjustment of the entire heat exchange structure by relying on the variable parameter b, and at the same time realize the combination of gas-liquid volume ratios in different units.

S2: Based on the Mathematica modeling platform, three-dimensional modeling of the hot melt gas-liquid two-phase heat transfer function is performed to construct a heat exchange unit body.

S3: Repeat step S2, and adjust the parameters of the heat exchange unit body in each cycle, adjust the internal structure of the heat exchange unit body, and change the gas-liquid volume ratio of the heat exchange unit body, until obtaining The heat exchange unit body that satisfies the preset gas-liquid volume ratio condition is regarded as the preferred unit body;

Equivalently, through the application of the Mathematica modeling platform, the geometric unit cell constructed based on the gas-liquid two-phase heat transfer function of the hot melt type is obtained, and the heat exchange unit cell with variable gas-liquid ratio is obtained by adjusting the function value. , and finally obtain the preferred unit cell.

S4: As shown in Figure 3, import the preferred unit body into the grasshopper parametric modeling platform, and obtain the set unit composed of the preferred unit body by rapidly iterating the array;

It is equivalent to importing the preferred unit body into the grasshopper parametric modeling platform, and on the basis of the original monomer, the three-dimensional array of xyz axis quickly realizes the structural filling inside the basic heat exchange body, its unit cell size and crystal The number of cells is regarded as the basic parameter.

S5: Repeat step S4, and calculate the surface area and mass of the aggregated unit in each cycle until the aggregated unit with the best surface area and quality is obtained as the preferred aggregate; the optimal aggregate can be obtained by setting the number of repetitions gather. Among them, the surface area and mass are optimal, and the evaluation is based on the larger the surface area and the smaller the mass.

Equivalently, the basic area and volume references are obtained through parameterized rapid iteration, and the optimal set that meets the requirements is obtained by using the function fitting and the screening mode of the bisection method.

S6: in the simsolid platform, perform mechanical simulation on the preferred set, so as to perform stress optimization;

It is equivalent to importing the existing preferred set into the simsolid platform for mechanical simulation. In the basic existing pressure environment, through analysis and optimization, by increasing the wall thickness and other means, a preferred set of thicknesses that meets the requirements is obtained. The mathematical modeling analysis basically meets the objective requirements of gas-liquid area ratio and heat exchange area ratio.

S7: 3D printing evaluation is performed on the optimal set after stress optimization, so as to perform 3D printing optimization;

It is equivalent to further additive manufacturing evaluation of the preferred set, and process production evaluation under the premise of meeting the requirements of heat exchange efficiency and heat exchange area. By adding welded walls and other means, the above preferred set has certain printing conditions.

S8: As shown in Figure 4, the optimized set of 3D printing is integrated through the rhino&grasshopper platform to obtain the final heat exchanger structure that meets the preset task requirements.

Equivalently, the last step of integration operation is performed on the basis of the optimal set obtained in step S7, and the parameter modeling advantages of the rhino&grasshopper platform are used to integrate all the parameter models in the previous part, and the final result based on the hot melt type gas-liquid two-phase is obtained. The optimal result of the heat exchange parameter adjustment that meets the task requirements, using parameter linkage, in this embodiment, the heat exchange surface area is increased by 26%, and the overall weight is reduced by 16%.

The iterative principle and structure principle of the heat exchanger structure optimization method of this embodiment will be described in detail below.

1. The principle of iteration

Since it is a gas-liquid two-phase heat exchanger, it is necessary to strive to print a unit with the largest possible volume and capacity within the printable range with the least mass while satisfying the basic gas-liquid volume ratio. Therefore, it is necessary to perform surface water pressure simulation analysis for a single unit cell with a certain surface area and a certain gas-liquid ratio controlled by certain parameters.

Adjust the parameters of the gas-liquid ratio parameter unit cell model required to meet the target, and then through the rapid iterative array, get the set unit composed of the preferred unit body, estimate the surface area and volume of the unit and compare it with the target. Step through the cycle, and finally obtain a preferred set with a mass smaller than the original model and a surface area larger than the original model (that is, a model with the lightest possible mass and the largest possible surface area is obtained under the condition of minimum printing accuracy).

After fine-tuning, enter simsolid to analyze the surface water pressure. For weak parts, increase the thickness slightly or as a whole to relieve stress concentration (structure optimization), and then conduct 3D printing evaluation as a whole.

2. Structural principle

As shown in FIG. 5 , in this embodiment, the heat exchange unit body constructed based on the hot melt gas-liquid two-phase heat transfer function forms two mutually independent flow channels (hereinafter referred to as gas-phase channels and liquid channels), The volume of the two channels of the unit body is measured by the software, and the ratio of the volume of the gas phase channel to the volume of the liquid channel is 3:1.

Combined with the dense distribution of the hot melt gas-liquid two-phase heat transfer function structure in space, and according to the expression of fluid convection heat transfer Q=hΔT×S, (h is the heat transfer coefficient (W/K m2), Q is the amount of heat transfer, ); it is concluded that the primary method to improve the heat transfer is to increase the gas-wall contact area S. This distribution of gas-liquid ratio effectively increases the gas-wall contact area per unit volume and greatly improves the heat transfer efficiency.

According to the software estimation, taking the traditional wave heat exchanger as an example, the design and surface area of the waterway grid have no effect on the heat exchange in essence. According to the analysis, it plays the role of turbulent flow of the water path to improve the heat transfer coefficient h, evenly divide the cooling water flow and support the tube wall, but does not effectively increase the heat exchange surface area.

Based on the implementation case analysis of this "hot melt type gas-liquid two-phase heat transfer function structure", the walls of the structure body in the implementation case can all act as heat exchange generating surfaces, and the material utilization rate is nearly 100%, which greatly improves the gas and gas. -Wall contact area, thus improving heat transfer efficiency.

As shown in FIG. 6 , the structure of the heat exchanger in this embodiment relies on the high symmetry and periodicity of the combination of sine and cosine functions to form the following characteristics: the gas-phase channels are arranged in rows and columns with a distribution law similar to a sine function, forming independent The gas phase channel is the same; the liquid flow channel is also arranged in the same arrangement rule in the remaining space. The two form an independent and complete combination of rows and columns, showing an adjacent relationship on the plane and overlapping relationship in space. At the same time, the two do not alternate with each other.

The cross-section of the flow channel of the heat exchanger obtained in this embodiment always exhibits a highly periodicity of the sine-cosine function, and the cross-sectional area ratio always strictly conforms to the ratio of the gas-liquid ratio. The structural wall of the heat exchange core exists between the gas phase channel and the liquid channel, and the heat exchange occurs on the exchange structure wall.

The wall thickness of the heat exchanger structure designed in this embodiment is 0.3mm, and the edge length of the unit body is 0.425*pi(mm). , the heat exchange core structure in this embodiment can withstand a liquid stress of 10.5 bar, and has a strong structural bearing capacity.

Specific heat transfer principle:

As shown in Figure 7, the liquid flows into the heat exchange core from the liquid channel below the figure, and the two ends are limited by the liquid sealing plates, and flow in the liquid flow channel of the heat exchange core. The gas enters the structure from the places where the two ends are not connected to the sealing plate, and flows into the gas phase channel. The gas and liquid flow in their respective flow channels, and through the connection of the holes between the layers, they are staggered in plane and staggered in space.

When the liquid reaches the bottom, it is pressed into the liquid channel shown above by relying on the liquid pressure, and is forced out of the liquid channel to the water outlet in the way of entering the structural core.

The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and changes according to the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the prior art according to the concept of the present invention shall fall within the protection scope determined by the claims.

Claims (9)

1. a heat exchanger structure optimization method based on hot melt type gas-liquid two-phase heat exchange structure, is characterized in that, comprises the following steps: S1: According to the hot-melt gas-liquid two-phase heat exchange structure, based on the sine and cosine functions, construct the hot-melt gas-liquid two-phase heat transfer function; S2: carry out three-dimensional modeling of the hot melt type gas-liquid two-phase heat transfer function to construct a heat exchange unit body; S3: Repeat step S2, and adjust the parameters of the heat exchange unit body in each cycle, adjust the internal structure of the heat exchange unit body, and change the gas-liquid volume ratio of the heat exchange unit body, until obtaining The heat exchange unit body that satisfies the preset gas-liquid volume ratio condition is regarded as the preferred unit body; S4: Obtain a set unit composed of the preferred unit body by rapidly iterating the array; S5: Repeat step S4, and calculate the surface area and mass of the aggregate unit in each cycle, until the aggregate unit with the best surface area and quality is obtained as the preferred aggregate; S6: perform mechanical simulation on the preferred set, so as to perform stress optimization; S7: 3D printing evaluation is performed on the optimal set after stress optimization, so as to perform 3D printing optimization; S8: Integrate the optimized set of 3D printing to obtain a final heat exchanger structure that meets the preset task requirements; The expression of the hot melt type gas-liquid two-phase heat transfer function is: XL=x-bCos[(x/2)^2] YL=y-bCos[(y/2)^2] ZL=z-bCos[(z/2)^2] p1=ContourPlot3D[Cos[XL]Sin[YL]+ Con[YL]Sin[ZL]+Cos[ZL]Sin[XL]=0, {x,-Pi,Pi},{y,-Pi,Pi},{z,-Pi,Pi}] In the formula, p1 is the hot melt gas-liquid two-phase heat transfer function, ContourPlot3D[*] is the three-dimensional space transformation function, x is the x-axis coordinate value, y is the y-axis coordinate value, z is the z-axis coordinate value, and b is the variable parameter. 2. The method for optimizing the structure of a heat exchanger based on a hot-melt gas-liquid two-phase heat exchange structure according to claim 1, wherein in step S3, parameter adjustment is performed on the heat exchange unit body, Specifically, by adjusting the variable parameter b, the parameters of the heat exchange unit are adjusted. 3. a kind of heat exchanger structure optimization method based on hot melt type gas-liquid two-phase heat exchange structure according to claim 1, is characterized in that, in step S5, described surface area and quality are optimal, based on surface area more. The larger and the smaller the mass is evaluated. 4. The method for optimizing the structure of a heat exchanger based on a hot melt gas-liquid two-phase heat exchange structure according to claim 1, wherein in step S6, the means for optimizing the stress comprises increasing the wall thickness . 5. The method for optimizing the structure of a heat exchanger based on a hot-melt gas-liquid two-phase heat exchange structure according to claim 1, wherein in step S7, the means of 3D printing optimization includes adding welding wall. 6. A heat exchanger structure optimization method based on a hot melt type gas-liquid two-phase heat exchange structure according to claim 1, characterized in that, in step S2, based on the Mathematica modeling platform, for the hot melt Three-dimensional modeling of the bulk gas-liquid two-phase heat transfer function. 7 . The method for optimizing the structure of a heat exchanger based on a hot melt gas-liquid two-phase heat exchange structure according to claim 1 , wherein the step S4 is specifically: introducing the preferred unit body into a grasshopper In the parametric modeling platform, through the rapid iterative array, the set unit composed of the preferred unit body is obtained. 8. The method for optimizing the structure of a heat exchanger based on a hot-melt gas-liquid two-phase heat exchange structure according to claim 1, wherein in step S6, in the simsolid platform, the preferred set is performed Mechanical simulation. 9. a kind of heat exchanger structure optimization method based on hot melt type gas-liquid two-phase heat exchange structure according to claim 1, is characterized in that, in step S8, through rhino&grasshopper platform integration 3D printing optimized preferred set .

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