Based on HRP-IV rapid prototyping machine,a mathematical model of tube radiation heating system was established to simulate heating installation location and to calculate angle coefficient of all work areas.

In order to study the infrared radiation characteristics of the targets,the solution methods of radiation heat transfer angle coefficients in different cases are discussed simply with practical examples in this paper.

The integral equations for calculating the angle factors between radiant tubes and between radiant tube and furnace wall are introduced and the numerical calculations are made.

Based on the calculation of the angle factors for radiation exchange and considering the radiation extinction caused by the absorption of the partici- pating media, a set of governing equations of the combined radiation and condu- ction as well as the radiation equilibrium in a two-dimensional rectangular enclo- sure are deduced in this paper.

The paper describes why the imaging fuze uses the principle of circle scan imaging and how it can get the plane target image,the paper provides the calculation methods of the power of the infrared imaging detector and the gray of target infrared image,including the calculation of the angle factor between detector element and plane skin and how to resolve the problem of image dege weakness.

Applying Stokes theorem and boundary element theory, the basic equation of the radiation angle factors and the mutual radiation area for calculating radiation heat transfer is deduced.

To get another method of calculating radioactive transfer coefficient, based on the concept of angle factors, the radioactive transfer coefficient was calculated by iteration method in light of the theory of energy conservation and of Lambert body assumption.