Research On Thermal Insulation And Thermal Deformation Of A Satellite Honeycomb Sandwich Plate

The metal honeycomb sandwich plate is an important part of the outer wall of the satellite module.It has the characteristics of good mechanical properties,noise reduction,energy absorption and heat insulation,so that it is widely used in the space field,such as the passive thermal protection system of satellite.The metal honeycomb sandwich structure is composed of three parts: the upper layer,the lower panel and the middle core layer.Among them,the upper and lower two panels are thinner,mainly bearing various loads inside the surface including the temperature load,and the middle core layer is a positive six prism tubular thin-walled structure,which mainly plays the role of support and heat insulation.Because of the complexity of the metal honeycomb sandwich plate structure,it is difficult to establish the finite element model.At the same time,in order to improve the computational efficiency,it is necessary to establish the thermal equivalent model of the sandwich plate.In this paper,by equivalent mechanical parameters of honeycomb core,the thermal equivalent model of honeycomb sandwich plate was established.The thermal equivalent model of honeycomb was verified by thermodynamic analysis.The main contents of this article are as follows:(1)Determination of reasonable equivalent model parameters from the perspective of thermal analysis.Based on the equivalent theory of sandwich panels,the finite element model of honeycomb sandwich plate is established,and the equivalent Geix coefficients and equivalent thermal expansion coefficients of honeycomb equivalent cores in x,y,z three directions are deduced.(2)The effects of geometrical parameters of honeycomb sandwich plate on heat conduction and thermal deformation are explored.The variation of temperature and displacement of cellular structure under different geometrical parameters is calculated.The results show that the heat insulation effect of honeycomb plate is mainly influenced by cell height and thickness,and thermal deformation is mainly affected by cell Bingchang height.(3)A thermal equivalent plate model is established to replace the metal honeycomb sandwich plate.Heat conduction and thermal deformation analysis of the detailed sandwich plate model and equivalent plate model are carried out respectively.The results show that the heat conduction error of two models is less than 3% and the thermal deformation error is not more than 6%,so the equivalent plate can replace the honeycomb sandwich plate for thermal analysis under certain conditions.(4)The thermal equivalent model is applied to the whole satellite simplified model,and the heat conduction analysis and thermal deformation analysis are carried out.The results show that the thermal protection facilities of negative y-plate and negative z-plate are weaker,so as to ensure the normal operation of single machine,the protective device should be installed in the corresponding position.The analysis shows that the roof of the load compartment,the negative z plate of the load cabin and the negative y plate of the In order to ensure the normal work need to install the reinforcement in the corresponding position of the load compartment to improve the rigidity of the structure.This paper provides a simplified thermal equivalent model for honeycomb panels,which can shorten the thermal analysis time of the whole star.It is helpful to improve the modeling efficiency and calculation efficiency of the whole star thermodynamic analysis,and to shorten the design cycle of the satellite.At the same time,the thermodynamic analysis results of the whole star provide some data support for the thermal design of the satellite.