Initial tests, TGLFNN (solid) vs QLKNN (dashed)

• All tests run by modifying test_iterhybrid_predictor_corrector.py.
• Note TGLFNNukaea training data may not cover ITER domains, so take with a pinch of salt.
• In TGLFNNukaea, VEXB_SHEAR input set to 0 - I wasn't sure what to do with this, as I believe the expression for ExB shear either needs an E-field or a rotation rate, neither of which are present in TORAX.
• TGLFNNukaea solid lines, QLKNN dashed lines.

Te only

Te, Ti

Te, Ti, psi

Te, Ti, psi, ne

Conclusions

• Something wrong in calculation of particle diffusivities and convectivities from fluxes?
• Thermal diffusivities seem pretty good, behaviour broadly matching QLKNN

In TGLFNNukaea, VEXB_SHEAR input set to 0 - I wasn't sure what to do with this, as I believe the expression for ExB shear either needs an E-field or a rotation rate, neither of which are present in TORAX.

This is fine for now. Rotation in TORAX is coming this Q3.

TGLFNNukaea solid lines, QLKNN dashed lines.

1. No need for Te only. It doesn't add much beyond Te+Ti

2. I think that the TGLF "transport barrier" at rho<0.4 (especially for Te+Ti+psi) is due to the negative magnetic shear. In QLKNN we reduce that impact with the avoid_big_negative_s flag which is True by default. I think this exasperates the difference. From comparisons to higher fidelity modelling we know that slab modes are underrepresented by QuaLiKiz which should still play a role at low/negative magnetic shear, hence this choice which is also in QuaLiKiz itself. So either we make something similar for TGLF and TGLFNN (if it's also relevant for TGLF), or we turn that flag off in QLKNN for the comparisons, or just do the comparison for a case without negative magnetic shear.

3. Particle transport. OMG. Yeah that doesn't look right