Research On Aircraft Skin Temperature Field Calculation And 3D Infrared Model Generation Method

The infrared radiation calculation and scene simulation of the aircraft have important significance in infrared guidance.The infrared radiation of the aircraft is mainly divided into two parts,the radiation caused by the aerodynamic heating of the aircraft skin and the radiation generated by the engine and its exhaust system.Due to the complex calculation of the infrared radiation of the whole aircraft,this paper mainly considers the infrared radiation caused by the aerodynamic heating of the stealth aircraft skin.At present,when using the aircraft skin temperature field to simulate the infrared scene,it can not reflect the optical properties of different parts of the aircraft,and it is difficult to correct the simulation results.Firstly,this paper uses the FLUENT software in CFD(Computational Fluid Dynamics)to calculate the three-dimensional temperature field of the aircraft skin.Then this paper uses the principle of color coding to process the three-dimensional temperature to generate the infrared texture temperature channel.Finally,generated the aircraft skin three-dimensional infrared the model,which is applied in the calculation of the three-dimensional infrared radiation texture,can reflect the optical properties of different parts of the aircraft and facilitate the correction of the simulation results.The main research content of this article has the following aspects:(1)In order to perform infrared radiation calculation and scene simulation on the aircraft skin,this paper studies how to use FLUENT to calculate the aircraft skin temperature field.Firstly,the basics of fluid mechanics are introduced,including basic properties of fluids,control equations,and initial and boundary conditions.Then FLUENT's solution process is analyzed.3D max is used to model three-dimensional stealth aircraft and unstructured mesh is divided.Finally,FLUENT parameters are set to calculate the aircraft skin temperature field.(2)Infrared texture is the focus of infrared scene simulation.This article has deeply studied the method of generating infrared texture temperature channels using three-dimensional temperature data.Firstly,the relationship between three-dimensional model and two-dimensional texture mapping is analyzed,and a color coded table is produced and rendered to the aircraft skin surface.Then the relationship between three-dimensional temperature field and two-dimensional space is introduced,and two-dimensional temperature image corresponding to three-dimensional temperature field is generated.Finally,by using the principle of color coding,by adjusting the camera's position,orientation,and other physical quantities,the rendered map and the two-dimensional temperature image are matched,and the two-dimensional temperature data is mapped onto the color coding table,and the dead pixels are blurred to be processed as a temperature channel data of infrared texture.(3)The aircraft 3D infrared model generation process is studied.Firstly,introducing the infrared texture encoding format,the different areas of the aircraft's material,temperature and emissivity are stored in the RGB three channels.Then combined with the aircraft model generates the aircraft's three-dimensional infrared model.Finally,use of three-dimensional rendering engine OGRE to generate high-realistic infrared Image,calculation of aircraft infrared radiation under different flight attitudes,and analysis of radiation results.According to the correspondence of the infrared textures of the three channels,the simulation results can be modified.