Question 22.4: Suppose that an S8 method is to be used to solve the neutron......

Introduction to Nuclear Reactor Physics [1368692]

Suppose that an $S_8$ method is to be used to solve the neutron transport equation in one dimension instead of an $S_4$ method.
How many more discrete angles will have to be used at each mesh point in this case?

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From the equations we presented earlier, the number of ordinates (discrete angular directions) in a one-dimensional $S_N$ method varies as N²/4 + N, where N is the order of the method. Hence, in one dimension, an $S_8$ method will require N²/4 + N separate ordinates. If N = 8, this is a total of 24 ordinates. From our previous discussion, this is a total of three times more ordinates than $S_4$ method (N = 4) uses

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