Radiant characteristics evaluation and structural parameter optimization design of V-grooved surface blackbody

Surface blackbody as standard radiation source is used extensively and increasingly in calibrating various infrared instruments in IR detection and imaging etc. However, so far there has been no in-depth study on the radiant characteristics evaluation methods for various structural surface blackbodies and the relationship between effective emissivity and structural factors In this paper, a radiant characteristics calculation method for V-grooved surface blackbody was presented based on Monte Carlo method (MCM). The exactitude of MCM was first approved by comparison with precise Bedford method. Then this method was applied to V-grooved surface blackbody, and the effects of structural factors on effective emissivity were analyzed. The results demonstrate that effective emissivity and its homogeneity are improved when small grooved angle and high intrinsic effective coating material are adopted, and higher effective emissivity and better uniformity can be obtained when a guarded sleeve is applied. It is possible to conclude that for general application, the grooved angles of 45° and 60° can lead to satisfactory effective emissivity and uniformity; to obtain higher radiant characteristic, smaller grooved angle is required, but the intrinsic emissivity of coating must be greater than or equal to 0.8; to achieve ideal radiant characteristic, it is essential to apply a guarded sleeve with the slenderness ratio of 2.