Study On The Characteristic Of Infrared Radiation From Carbon Fiber By The Finite-difference Time-domain Method

Carbon fiber and its composite materials have low desnity, low cost, anti-fatigue,low thermal conductivity and expansion coefficient, In recent decades, it has been rapiddevelopment. It is widely used in spacecraft thermal protection and stealth aircraft andother defense sectors.The study on the characteristic of infrared radiation from carbon fiber focuses onexperimental measurements, so in this paper, the characteristic of infrared radiation fora single Carbon fiber and two common carbon fiber woven structure of2D and2.5Dwere studied from the theory, based on Maxwell’s equations and combined withfinite-difference time-domain method. Specific studies are as follows:Firstly, we have simplified and created a single particle of carbon fiber geometry,founded applicable to the complex refractive index of the carbon fiber, introduced aplane electromagnetic wave by TF/SF, and validated using the FDTD method feasibilityof particle scattering problem by comparing with the Mie theory. Scattering intensity,absorption factor and scattering factor were calculated. We analyzed the impact ofradiation characteristics by radius of carbon fiber, refractive index of background andcomplex refractive index of the carbon fiber.Then, we established the calculation model of2D and2.5D carbon fiber wovenstructure. Scattering intensity, absorption factor and scattering factor of them werecalculated. We analyzed the impact of radiation characteristics by radius of carbon fiber,vertical layers, lateral space, longitudinal space, refractive index of background andcomplex refractive index of the2D and2.5D carbon fiber woven structure.Finally, we proved that treating the2.5D woven structure like bulk is not feasible.And we demonstrated that the infrared radiation characteristics of2.5D carbon fiberwoven structure is superior to2D woven structure from2.5μm to10μm through thecomparison of the data.