Calculation of shape factors between parallel ring sectors sharing acommon centerline

7, cm £;, ni}, n1 — cosines (i.e., direction cosines) of angles between normal to d/4 7 and x-, y-, and z- axes, respectively *2> y>2> Z2 = cartesian coordinates of point on periphery of surface 2, cm s = distance between dA l and point on periphery of surf ace 2, cm r0> rf = outer and inner radii, respectively, of surface 2, cm r = radial coordinate in plane of surface 2, cm h = vertical distance between surfaces 1 and 2, cm p = radial coordinate in plane of dA /, cm /3 = angular displacement of dA 7 with respect to pr