Thermal Radiation Calculation Of Complex Surface Based On Triangulation And Gauss Integral Method

Fire accidents happened frequently which have brought serious loss of life and property to the state and people,and more and more attention has been paid to them.Thermal radiation is an important way of heat transfer in fire,so the study of thermal radiation is of great significance.In the actual fire scene,most of the thermal radiation emission objects and the receiving objects are complex shapes,and their surfaces are mostly irregular plane or even curved surface.Previous thermal radiation calculation methods often have low accuracy and calculated slowly.In this paper,the finite element method based on Gauss integral formula was used to calculate the thermal radiation between complex surfaces,it not only had high calculation accuracy,but also had very fast operation speed.This paper fully adopt the idea of finite element method,and combined the triangulation of the complex surface and the Gauss integral method,and used the Delaunay triangulation algorithm based on mapping method to triangulate the complex object surface,so the thermal radiation calculation between the whole surface was transformed into the angular coefficient calculation between the small triangular elements,which greatly reduced the difficulty of calculation meanwhile effectively improved the accuracy of calculation.The author used Gauss integral method to calculate and verify several thermal radiation models with theoretical solution.Through error analysis,it was found that the error can be kept at about 1% except for radiation model with common edges.No matter how dense the triangles were,the calculation program can guarantee the extremely high operation speed.Moreover,for the vertical computing model with common edges,the calculation error can be significantly reduced by increasing the number of triangles.To further simulate actual fire scene,established two or more curved surface radiation models and used Gauss integral method to calculate their angular coefficients,then obtained the heat radiation value by using the radiation heat transfer formula.The results show that even for the complex radiation model between several surfaces,Gauss integral method can also be used to efficiently calculate the thermal radiation angular coefficient,and it proved that the stability and applicability of the method.