View Factors between Disc/Rectangle and Rectangle in Parallel and Perpendicular Planes

ANALYSIS of radiation heat transfer requires expressions or data for view factors between finite surfaces. A review of the literature shows that a comprehensive catalog of view factors [1] provides expressions or data for several differential and finite geometrical configurations; closed form solutions have been presented by Ehlert and Smith [2] for view factors between two rectangles when they are perpendicular to each other and all the edges are either parallel or perpendicular. The catalog of view factors [1] also shows that expressions or data for several pairs of finite surfaces are not available, which are quite common in many applications. Hence, presently, three configurations of finite surfaces have been considered: the view factor between 1) a disk and a rectangle on parallel planes (as shown in Fig. 1); 2) a disk and a rectangle in perpendicular planes, when the disk is placed on the plane containing the rectangle with its edges either parallel or perpendicular to the plane of the disk (as shown in Fig. 1); 3) rectangles in perpendicular planes, when an edge of one rectangle is placed on the plane containing the other rectangle, which is placed arbitrarily (as shown in Fig. 2). Closed form solutions have been developed to the extent possible, and correlations have been presented for three specific cases, after evaluating the nonintegrable terms numerically.