Version 1.2

Version 1.2 - Transonic correction and analytical gradients

This version mainly features a transonic solver and analytical pressure derivatives.

Changes

• Add transonic correction
• Add analytical gradients
• Add feature to deform the body
• Fix calculation of motion-induced velocity and unsteady pressure
• Refactor APIs and utilities

Notes

Transonic correction
The unsteady pressure solution can now be corrected by higher-fidelity data (typically obtained from CFD) to include transonic and viscous effects.
Analytical gradients
Although CoDiPack works well, its memory footprint is too large for practical unsteady cases (see #6). Analytical pressure and aerodynamic forces gradients have therefore been implemented so that flutter constrained optimization can be performed within a reasonable computational time.
Body deformation
The body nodes can now be set to new positions for aeroelastic and optimization purposes.
Formulation fixes
The calculation of the surface velocity induced by a rigid pitching motion has been corrected to use original instead of compressible coordinates. Additionally, a mistake in the calculation of the unsteady pressure coefficient has been fixed.
Refactoring
The default values in the API have been refactored. The slicing utility now also outputs z-coordinates.

Tests

• Ubuntu 22.04 (gcc 11, python 3.10)

sdpm/api/core.py

@@ -58,14 +58,14 @@ def init_sdpm(cfg, use_ad=False):
         raise RuntimeError('Symmetric (half) geometric model cannot be used with nonzero angle of sideslip (AoS)!\n')
 
     # Mesh
-    pars = {} if 'Pars' not in cfg else cfg['Pars']
+    pars = cfg.get('Pars', {})
     _msh = MeshLoader(cfg['File']).run(pars)
     _wrt = sdpm.GmshExport(_msh)
 
     # Problem
-    aoa = 0 if 'AoA' not in cfg else cfg['AoA'] * math.pi / 180
-    aos = 0 if 'AoS' not in cfg else cfg['AoS'] * math.pi / 180
-    minf = 0 if 'Mach' not in cfg else cfg['Mach']
+    aoa = cfg.get('AoA', 0.) * math.pi / 180
+    aos = cfg.get('AoS', 0.) * math.pi / 180
+    minf = cfg.get('Mach', 0.)
     _pbl = sdpm.Problem(_msh)
     _pbl.setGeometry(cfg['s_ref'], cfg['c_ref'], cfg['x_ref'], cfg['y_ref'], cfg['z_ref'], cfg['Symmetry'])
     _pbl.setFreestream(aoa, aos, minf)
@@ -85,7 +85,7 @@ def init_sdpm(cfg, use_ad=False):
     _pbl.addBody(_bdy)
 
     # Solver
-    vrb = cfg['Verb_lvl'] if 'Verb_lvl' in cfg else 1
+    vrb = cfg.get('Verb_lvl', 1)
     _sol = sdpm.Solver(_pbl, vrb) if 'Transonic_pressure_grad' not in cfg else sdpm.SolverTransonic(_pbl, vrb)
     _adj = sdpm.Adjoint(_sol) if use_ad else None