Thermal Response Function Method For Black Box Modeling Of Target Surface Temperature

Thermal analysis and thermal design are the key technologies in many high-tech fields,such as military equipment,aerospace and electronics.The main purpose is to control the temperature of the thermal analysis target within the required range.At present,the theory of thermal analysis is mainly aimed at the target with internal structure and thermal physical properties known,while the research on how to model the temperature of black box targets whose internal structure and thermal physical properties are unknown is still lacking.To treat this problem,this paper establishes a thermal analysis theory for modeling the surface temperature of black box targets,i.e.,the thermal response function theory.The defined thermal response function is a measurable physical quantity of black box targets.Numerical verification and preliminary experimental verification are carried out respectively.Through rigorous mathematical derivation,a theory of modeling the surface temperature of black box target,i.e.,the thermal response function theory is established.This theory can realize the thermal analysis of the surface temperature of a black box target by measuring the thermal response signal of the black box target applied with the external exciting heat flow.This theory gives the basic form of black box target thermal response function theory.Based on this basic form,this paper studies the radial-basis-function form and the square-wave form of the thermal response function theory according to the different forms of exciting heat flow.Numerical verification has been completed for the radial-basis-function form and the square-wave form of the proposed thermal response function theory.For a black box target,the thermal response function of the target is obtained using the exciting heat flow,and then the target temperature is calculated by the thermal response function theory,which is noted as T*;The temperature obtained by the finite volume method is noted as T*,in the case of the internal structure and thermal physical properties of the black box target are"known".Compare and verify the temperature T*and T*obtained by the two methods under different external heat flow boundary conditions.Numerical verification shows that the thermal response function theory proposed in this paper can achieve effective thermal analysis of a black box targets within a certain error range.Preliminary experimental verification has been completed for the square-wave form of the proposed thermal response function theory.The thermal response function experiment was designed,and the thermal response function of a black box target used in the experiment was measured.Based on the thermal response function measured in the experiment,calculate the temperature of the black box target under the“arbitrary”external heat flow given in the experiment and noted it as T;for the black box target under the“arbitrary”external heat flow given in the experiment,the measured temperature of the experiment is noted as _mT,compare and verify T and _mT.The experimental results show that the designed thermal response function experiment can get the thermal response function of the target under the exciting heat flow;using the thermal response function theory proposed in this paper and the thermal response function obtained by the experiment,it is preliminarily proved that this scheme is feasible to perform surface thermal analysis on a black box target.