Triangular Subdivision for the Computation of Form Factors

Abstract

In lighting, daylighting, and radiation heat transfer analyses, numerical values of form factors of different configurations are required. Improvement in accuracy and efficiency is the motivation behind the development of most numerical methods. This paper presents an approach for numerical computation of form factor between two polygons based on dividing each polygon into triangles and subdividing each triangle into identical incremental triangles. The approach is applied to evaluate the double area integral of the form factor under deterministic and Monte Carlo schemes. These two, and another two methods based on use of incremental rectangles together with a classical Monte Carlo method, are used to obtain numerical values of form factors in four test configurations. The results of the five methods are compared in terms of accuracy and efficiency. Comparisons are also made with known results from literatures. It is shown that the proposed method is simple to apply and is accurate and efficient.