Nuclear Science and Engineering / Volume 182 / Number 2 / February 2016 / Pages 166-180
Technical Paper / dx.doi.org/10.13182/NSE14-49
Using two different methods, angular quadrature sets are developed with greater than about 1000 angles per octant to reduce ray effects in three-dimensional (3-D), discrete ordinates radiation transport calculations with large air or void regions. Quadrature sets from both methods are evaluated in two distinct 3-D models sensitive to quadrature details and are shown to behave reasonably well. The first method is a previously described method that is examined here in 3-D. The second method produces quadrature sets that have quadrature directions approximately evenly spaced over the entire surface of the unit sphere.