Surface Blackbody Radiation Characteristies Analysis And Design

This paper introduces the theory of thermal radiation and blackbody cavity. The analysis of the blackbody cavity of the main integral equation method and Monte Carlo method are introduced. The Monte Carlo radiation model is established. The method of determining the location of an emitting point and a ray direction, judging if it is absorbed or reflected are introduced. Blackbody cavities with small apertures applied in industry usually work in high temperature. With developments of science and technology, blackbody radiant sources wording under low temperature range are needed. The radiant sources with large apertures or surface blackbody can satisfy the requirements. The radiation characteristics of surface radiant sources with complex radiant surfaces such as V-groove or honeycombed are difficult to be evaluated by precise methods. The Monte Carlo method is adopted to simulate the radiation of surface sources. In this paper, we set up the Monte Carlo models proper to circular V-groove surfaces and six prism honeycombed surface, use full beam tracking simulation of radiation to calculate their emission rates. Due to the convergence of Monte Carlo method is slow, large number samples are needed when we take tracking rays to simulate. The radiation characteristics of radiation sources under different sampling points, temperatures, mirror reflecting surfaces are calculated and analysed. For V-groove surface, effective emissivities under the cone angle of 30o, 45o, 60o, 90o are calculated, for six prism honeycomb surface, effective emissivities with prism heights from 1.0 to 3.0, by increase of 0.2; side lengths from1.0 to 3.0 by an increase of 0.5 are calculated. Taking these factors across the radiation properties of the structural design of radiation sources. To improve the surface properties of radiation sources of radiation, external radiation sources in the face of our added sheath. At this point surface radiation and sheath form a cavity, using the traditional method of calculation of blackbody cavity integral equation method to calculate the emissivity of the cavity is given the appropriate length of the sheath. The radiant source is heated by heat pipe and PID method is used in the temperature control system and its simulation is performed.