Do not scale or clip Pereverzev-Corrigan stabilization coefficients in ADAPTIVE_TRANSPORT mode. - #2496
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Do not scale or clip Pereverzev-Corrigan stabilization coefficients in ADAPTIVE_TRANSPORT mode.#2496copybara-service[bot] wants to merge 1 commit into
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…n ADAPTIVE_TRANSPORT mode. In `PedestalModelOutput.modify_core_transport`, `_scale_coeffs` clips and scales down the 4 standard diffusive/convective channels (`chi_face_ion`, `chi_face_el`, `d_face_el`, `v_face_el`) while leaving the Pereverzev inward counter-pinch heat convection channels (`full_v_heat_face_ion`, `full_v_heat_face_el`) untouched. Applying `_scale_coeffs` to `core_transport.pereverzev` breaks the exact zero-net-flux cancellation of the Pereverzev-Corrigan preconditioner inside the H-mode pedestal, injecting an unphysical inward heat pinch in `initial_guess_mode="linear"` and predictor-corrector steps. Remove `modified_pereverzev = _scale_coeffs(core_transport.pereverzev)` and pass `core_transport.pereverzev` directly in `PedestalModelOutput.modify_core_transport`. This preserves exact Pereverzev flux cancellation across the entire plasma and reduces `test_iterhybrid_lh_transition` solver steps from 631 to 86 (outer solver iterations from 1,226 to 120; inner solver iterations from 7,458 to 959) while producing identical converged profiles (mean relative difference 0.019% on T_i, 0.013% on T_e, 0.016% on W_thermal_total). PiperOrigin-RevId: 985373534
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Do not scale or clip Pereverzev-Corrigan stabilization coefficients in ADAPTIVE_TRANSPORT mode.
In
PedestalModelOutput.modify_core_transport,_scale_coeffsclips and scales down the 4 standard diffusive/convective channels (chi_face_ion,chi_face_el,d_face_el,v_face_el) while leaving the Pereverzev inward counter-pinch heat convection channels (full_v_heat_face_ion,full_v_heat_face_el) untouched. Applying_scale_coeffstocore_transport.pereverzevbreaks the exact zero-net-flux cancellation of the Pereverzev-Corrigan preconditioner inside the H-mode pedestal, injecting an unphysical inward heat pinch ininitial_guess_mode="linear"and predictor-corrector steps.Remove
modified_pereverzev = _scale_coeffs(core_transport.pereverzev)and passcore_transport.pereverzevdirectly inPedestalModelOutput.modify_core_transport. This preserves exact Pereverzev flux cancellation across the entire plasma and reducestest_iterhybrid_lh_transitionsolver steps from 631 to 86 (outer solver iterations from 1,226 to 120; inner solver iterations from 7,458 to 959) while producing identical converged profiles (mean relative difference 0.019% on T_i, 0.013% on T_e, 0.016% on W_thermal_total).