LLNL/UEDGE

Inconsistency of thermal force coefficient alpha_e implementation in code vs equation in manual + references

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Describe the issue
Lines 5341-5344 in oderhs.m perform the calculation of the alpha_e thermal force coefficients with impurity species.

In the code, all terms in this equation use zi or zeffv:

alfe(ifld) = cfgte*2.2*zi(ifld)**2*(1+.52*zeffv) /
     .                      ( (1+2.65*zeffv)*(1+.285*zeffv)*zeffv )

But in the UEDGE manual (see Appendix A), the equation is given differently as:

alfe(ifld) = cfgte*2.2*zi(ifld)**2*(1+.52*z0) /
     .                      ( (1+2.65*zeffv)*(1+.285*zeffv)*zeffv )

using a z0 term in the numerator, where z0 = ne*zeff/nh − 1.

And both appear inconsistent with the two references cited in the manual for the coefficients. E.g. in Igitkhanov, all terms in alpha_e use zeff (including where zi term is used above).
No idea what the correct form should be, but looks like an inconsistency that would warrant some attention.