Modified Diffusion Synthetic Acceleration Algorithms

The diffusion synthetic acceleration (DSA) method is an iterative procedure for obtaining rapidly convergent numerical solutions of discrete ordinates problems. General P_L acceleration methods for L>1 are first considered to determine if DSA, which is equivalent to P₁ acceleration, is optimum. After determining that DSA appears to be the optimum P_L approach, it is then demonstrated that by also using standard techniques of matrix iterative acceleration, modest improvements can be made in DSA performance.