Question 22.5: Write down an explicit expression for the three components Ω......

Introduction to Nuclear Reactor Physics [1368692]

Write down an explicit expression for the three components $Ω_x, Ω_y, and Ω_z$ of the angular unit vector Ω that appears in the neutron transport equation when the transport equation is to be solved in the x and z directions and the azimuthal angle φ is zero.

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In this case, the angular directional vector Ω = i sin θ cos φ + j sin θ sin φ + k cos θ reduces to Ω = i sin θ + k cos θ, so the components are $Ω_x = i sin θ, Ω_y = 0, and Ω_z = k cos θ$ .

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