Heat flow uniformity optimization design method for profiling quartz lamp heater

Abstract

The invention belongs to the technical field of infrared radiation heaters, and discloses a heat flow uniformity optimization design method for a profiling quartz lamp heater, which comprises the following steps of: establishing a profiling quartz lamp heater model; determining to-be-optimized optimization variables of the profiling quartz lamp heater model according to the structure and the test piece of the established profiling quartz lamp heater model; setting an optimization target of the profiling quartz lamp heater model; setting constraint conditions in the optimization process; compiling an optimization design program based on an improved genetic algorithm; according to the method, the arrangement mode of the optimized profiling quartz lamp heater model for the complex test piece can be determined by optimizing the design program, optimizing the included angle between the adjacent modular quartz lamp heaters and optimizing the distance between the modular quartz lamp heaters and the surface of the test piece; the optimized profiling quartz lamp heater model can effectively improve the heat flux density uniformity of the modular quartz lamp heater to a test piece, and the test precision and the accuracy of aircraft surface temperature simulation are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of infrared radiation heaters, and in particular relates to a heat flow uniformity optimization design method for a profiled quartz lamp heater. Background Art

[0002] With the continuous development of science and technology, high Mach number aircraft face strong aerodynamic heating effects during service, causing the aircraft structure to bear severe high temperature loads. In order to ensure the safety and reliability of the aircraft structure in a high temperature environment, it is necessary to test and evaluate the structure through ground tests. Therefore, it is necessary to accurately simulate the high temperature loads faced by the structure in flight in a ground environment.

[0003] In the simulation of ground thermal environment, common heating methods include quartz lamp heating, graphite heating and arc wind tunnel heating, among which quartz lamp heating has been widely used in engineering practice due to its advantages of high heating rate, good heating stability, easy control and assembly, etc. Most existing quartz lamp heaters arrange the lamp tubes equidistantly according to the shape of the test piece. However, due to the coupling between heating modules, boundary cold zone effect and other factors, it is easy to cause a certain degree of non-uniformity in the heat flux on the surface of the structure, thereby affecting the test accuracy, and may cause inaccurate simulation of the aircraft surface temperature, thereby affecting the evaluation of the heat resistance of thermal protection materials; therefore, there is a problem in the prior art that the heat flux density received on the surface of the test piece is uneven, which is easy to affect the test accuracy and the accuracy of the aircraft surface temperature simulation. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for optimizing the design of heat flux uniformity of a contoured quartz lamp heater, which solves the problem in the prior art that the heat flux density received on the surface of the test piece is uneven, which in turn easily affects the test precision and the accuracy of the aircraft surface temperature simulation.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for optimizing the heat flux uniformity of a contoured quartz lamp heater comprises the following steps:

[0007] Build a model of a contoured quartz lamp heater;

[0008] According to the structure of the established profiling quartz lamp heater model and the test piece, the optimization variables to be optimized of the profiling quartz lamp heater model are determined;

[0009] Setting optimization goals for the contoured quartz lamp heater model;

[0010] Set constraints during the optimization process;

[0011] An optimization design program based on an improved genetic algorithm was written. Under the premise of constraints, the optimization design program iterated the permutations and combinations of different optimization variables by hybridization, mutation and screening to obtain the optimal permutations and combinations of different optimization variables suitable for the test piece, and optimized the contoured quartz lamp heater model according to the optimal permutations and combinations of different optimization variables.

[0012] The contoured quartz lamp heater model comprises a plurality of modular quartz lamp heaters placed in parallel, and any two adjacent modular quartz lamp heaters are rotatably hinged, and the angle between the two adjacent modular quartz lamp heaters is adjustable.

[0013] The optimized variables include the angle between two adjacent modular quartz lamp heaters and the distance between the modular quartz lamp heater and the surface of the test piece.

[0014] The optimization goal is the uniformity of the heat flux density distribution of the modular quartz lamp heater on the irradiated surface of the test piece.

[0015] The constraint condition is the preset target average heat flux density.

[0016] The optimization design program adopts the dynamic adjustment mutation probability method in the improved genetic algorithm and sets the convergence number as the convergence condition to converge the distance between the modular quartz lamp heating and the surface of the test piece;

[0017] The dynamic adjustment variation probability method is as follows: when the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is large, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is large;

[0018] When the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is small, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is small.

[0019] Beneficial effects of the present invention:

[0020] The present invention can optimize the angle between adjacent modular quartz lamp heaters and the distance between the modular quartz lamp heaters and the surface of the test piece through an optimization design program, and can determine the arrangement mode of the optimized profiling quartz lamp heater model for the complex test piece, thereby compensating for the heat flow at the edge of the test piece, and effectively improving the uniformity of the heat flux density of the modular quartz lamp heater to the test piece. The optimized profiling quartz lamp heater model can improve the test accuracy and the accuracy of the aircraft surface temperature simulation;

[0021] The present invention adopts a dynamic adjustment variation probability method to optimize the design of the radiation heating characteristics of the quartz lamp heater, so that the distance between the modular quartz lamp heater and the surface of the test piece converges early, thereby improving the stability and convergence speed of the algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 It is a flow chart of the optimization design method of the present invention;

[0024] Figure 2 It is a schematic diagram of the structure of the profiling quartz lamp heater model and the test piece of the present invention;

[0025] Figure 3 It is a schematic diagram of a contoured quartz lamp heater model before optimization of the present invention;

[0026] Figure 4 It is a cloud diagram of heat flux density distribution on the surface of the test piece before optimization of the present invention;

[0027] Figure 5 It is a schematic diagram of the optimized contoured quartz lamp heater model of the present invention;

[0028] Figure 6 It is a cloud diagram of heat flux density distribution on the surface of the optimized test piece of the present invention. DETAILED DESCRIPTION

[0029] 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.

[0030] like Figures 1 to 6 As shown, a method for optimizing the heat flux uniformity of a contoured quartz lamp heater comprises the following steps:

[0031] Build a model of a contoured quartz lamp heater;

[0032] According to the structure of the established profiling quartz lamp heater model and the test piece, the optimization variables to be optimized of the profiling quartz lamp heater model are determined;

[0033] Setting optimization goals for the contoured quartz lamp heater model;

[0034] Set constraints during the optimization process;

[0035] An optimization design program based on an improved genetic algorithm was written. Under the premise of constraints, the optimization design program iterated the permutations and combinations of different optimization variables by hybridization, mutation and screening to obtain the optimal permutations and combinations of different optimization variables suitable for the test piece, and optimized the contoured quartz lamp heater model according to the optimal permutations and combinations of different optimization variables.

[0036] The contoured quartz lamp heater model comprises a plurality of modular quartz lamp heaters placed in parallel, and any two adjacent modular quartz lamp heaters are rotatably hinged, and the angle between the two adjacent modular quartz lamp heaters is adjustable.

[0037] The optimized variables include the angle between two adjacent modular quartz lamp heaters and the distance between the modular quartz lamp heater and the surface of the test piece.

[0038] According to the optimization variables, optimization variables and constraints, an optimization design program based on the improved genetic algorithm is written. This optimization design program can search for different optimization variable values ​​in a given design space. Different values ​​of different variables are arranged and combined to form variable combinations, that is, individuals. Multiple individuals form a population library, and the best individuals of each generation are selected. The best genes of each generation are passed to the next generation through hybridization, mutation and screening, and finally the convergence target is met to obtain the optimal individual.

[0039] like Figure 2 As shown, it is a schematic diagram of the contoured quartz lamp heater model and the test piece structure in the embodiment of this aspect, the angles between any two adjacent modular quartz lamp heaters in any two groups are a and b respectively, and the distance between the modular quartz lamp heating and the surface of the test piece is h.

[0040] The optimization goal is the uniformity of heat flux distribution of the modular quartz lamp heater on the irradiated surface of the test piece;

[0041] The calculation formula for the uniformity of heat flux distribution on the irradiated surface of the test piece is:

[0042]

[0043] Among them, σ1 is the standard deviation of heat flux density in the irradiated surface, is the average heat flux density within the irradiation surface;

[0044] Calculate the average heat flux density within the irradiated surface When calculating, multiple measurement points can be set on the surface of the test piece, and the heat flux density of each measurement point must be included in the calculation;

[0045] The heat flux uniformity optimization design method of the profiled quartz lamp heater of the present invention optimizes the heat flux density distribution uniformity of the irradiated surface of the test piece, so that the heat flux density distribution uniformity of the irradiated surface of the test piece is higher and the heat flux distribution is more stable.

[0046] The constraint condition is the pre-set target average heat flux density;

[0047] During the optimization process, the target average heat flux density and the average heat flux density on the irradiated surface of the test piece The following relationship must be satisfied:

[0048]

[0049] Where E0 is the target average heat flux density, and ε is the allowable error of the heat flux density in the irradiation surface relative to the target average heat flux density.

[0050] The optimization design program adopts the dynamic adjustment mutation probability method in the improved genetic algorithm and sets the convergence number as the convergence condition to converge the distance between the modular quartz lamp heating and the surface of the test piece;

[0051] The dynamic adjustment variation probability method is as follows: when the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is large, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is large;

[0052] When the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is small, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is small.

[0053] During the iterative optimization process, the mutation probability is dynamically adjusted. In the specific calculation process, if the target average heat flux density is equal to the average heat flux density on the irradiated surface of the test piece, If the difference between the two is too large, the difference between them will be greater than the threshold δ0. At this time, the mutation probability of the first two genetic codes of the optimization variable h will be increased. With the iterative adjustment of h, until the set target average heat flux density is equal to the average heat flux density on the irradiated surface of the test piece, When the difference is less than or equal to the threshold δ0, the mutation probability of the first two genetic codes of variable h is reduced; the specific values ​​of the mutation probability are as follows:

[0054]

[0055] Where δ1 is the average heat flux density of the target and the average heat flux density of the irradiated surface of the test piece. The difference between the two, p0 is the initial mutation probability, p m is the dynamically adjusted mutation probability.

[0056] By adaptively adjusting the probability of variation, the average heat flux density of the irradiated surface of the test piece can be ensured to be The constraints are met as quickly as possible so that the distance between the modular quartz lamp heater and the surface of the test piece converges first, thereby accelerating the overall convergence speed and improving the algorithm calculation efficiency.

[0057] It should be noted that the target average heat flux density in this example is set to 50kw / m 2 , the allowable error ε of the heat flux density in the irradiation surface relative to the target average heat flux density is 1%;

[0058] The arrangement of the contoured quartz lamp heater model before optimization is as follows Figure 3 As shown in Figure 2, the heat flux distribution on the surface of the test piece before optimization is as follows: Figure 4 As shown, the arrangement scheme of the profiled quartz lamp heater is optimized by using the heat flow uniformity optimization design method of the profiled quartz lamp heater proposed in the present invention. Figure 5 As shown, compared with the two sides before optimization, the modular quartz lamp heaters are closer to the test piece to compensate for the heat flux density at the edge. The heat flux density distribution cloud diagram of the optimized test piece is as follows Figure 6 As shown, through Figure 6 and Figure 4 By comparison, calculations show that the uniformity of heat flux distribution on the irradiated surface after optimization in this embodiment is improved by 7.62%.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0060] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A method for optimizing the heat flux uniformity of a contoured quartz lamp heater, characterized in that: The following steps are involved: Build a model of a contoured quartz lamp heater; According to the structure of the established profiling quartz lamp heater model and the test piece, the optimization variables to be optimized of the profiling quartz lamp heater model are determined; Setting optimization goals for the contoured quartz lamp heater model; Set constraints during the optimization process; An optimization design program based on an improved genetic algorithm was written. Under the premise of constraints, the optimization design program iterated the permutations and combinations of different optimization variables by hybridization, mutation and screening to obtain the optimal permutations and combinations of different optimization variables suitable for the test piece, and optimized the contoured quartz lamp heater model according to the optimal permutations and combinations of different optimization variables.

2. The method for optimizing the heat flux uniformity of a contoured quartz lamp heater according to claim 1, characterized in that: The contoured quartz lamp heater model comprises a plurality of modular quartz lamp heaters placed in parallel, and any two adjacent modular quartz lamp heaters are rotatably hinged, and the angle between the two adjacent modular quartz lamp heaters is adjustable.

3. The method for optimizing the heat flux uniformity of a contoured quartz lamp heater according to claim 2, characterized in that: The optimized variables include the angle between two adjacent modular quartz lamp heaters and the distance between the modular quartz lamp heater and the surface of the test piece.

4. The method for optimizing the heat flux uniformity of a contoured quartz lamp heater according to claim 3, characterized in that: The optimization goal is the uniformity of the heat flux density distribution of the modular quartz lamp heater on the irradiated surface of the test piece.

5. The method for optimizing the heat flux uniformity of a contoured quartz lamp heater according to claim 4, characterized in that: The constraint condition is the preset target average heat flux density.

6. The method for optimizing the heat flux uniformity of a contoured quartz lamp heater according to claim 5, characterized in that: The optimization design program adopts the dynamic adjustment mutation probability method in the improved genetic algorithm and sets the convergence number as the convergence condition to converge the distance between the modular quartz lamp heating and the surface of the test piece; The dynamic adjustment variation probability method is as follows: when the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is large, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is large; When the difference between the current average heat flux density of the irradiated surface of the test piece and the target average heat flux density is small, the variation probability of the distance between the modular quartz lamp heater and the surface of the test piece is small.

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