1. Inputs

VortexAD uses an input dictionary to pass information to the main solver. The solver inputs build onto a default input dictionary; it is up to the user to provide any updated inputs in a python dictionary format. The input dictionary is stored above the PanelMethod class here, and is also shown below.

default_input_dict = {
    # flow properties
    'V_inf': 10., # m/s
    'Mach': None,
    'sos': 340.3, # m/s, 
    'alpha': None, # user can provide grid of velocities as well
    'rho': 1.225, # kg/m^3
    'compressibility': False, # PG correction
    'Cp cutoff': -5., # minimum Cp (numerical reasons)

    # mesh
    'mesh_path': default_mesh_path,
    'mesh_mode': 'unstructured',

    # collocation velocity
    'collocation_velocity': False,

    # panel method conditions
    'BC': 'Dirichlet',
    'higher_order': False,

    # solver and wake mode; steady is fixed, unsteady is prescribed or free
    'solver_mode': 'steady',
    'wake_mode': 'fixed',

    # partition size for linear system assembly
    'partition_size': 1,

    # GMRES linear system solve
    'iterative': False,
    
    # ROM options
    'ROM': False, # 'ROM-POD or ROM-Krylov

    # reusing AIC (no alpha dependence on wake) --> this only applies to fixed wake
    'reuse_AIC': False,

    # others
    'ref_area': 10., # reference area (l^2, l being the input length unit)
    'ref_chord': 1.,
    'moment_reference': np.zeros(3), 
    'drag_type': 'pressure' # pressure or Trefftz (not implemented yet)
}

The table below summarizes each input. This work is still in development; any inputs noted with (WIP) signify that they are a work in progress.

Key	Meaning	Default	Units	Shape/Type	Options
V_inf	Freestream velocity	10	m/s	scalar/vector/tensor	N/A
Mach	Mach number	None	None	scalar/vector/tensor	N/A
sos	Speed of sound	340.3	m/s	scalar/vector/tensor	N/A
alpha	Inflow angle	None	degrees	scalar/vector/tensor	N/A
rho	Fluid density	1.225	kg/m^3	scalar/vector/tensor	N/A
compressibility	Compressibility correction	False	N/A	string	(False, True)
Cp cutoff	Pressure coefficient minimum cutoff	-5.	None	scalar	N/A
mesh_path	Path to mesh file	path to this file	N/A	string	N/A
mesh_mode	Mesh type	unstructured	N/A	string	(structured, unstructured)
BC	Boundary condition	Dirichlet	N/A	string	(Dirichlet, Neumann (WIP))
higher_order (WIP)	Higher-order methods	False	N/A	bool	(False, True)
solver_mode	Steady or unsteady	‘steady’	N/A	string	(‘steady’, ‘unsteady’ (WIP))
wake_mode	Mode for wake	‘fixed’	N/A	string	(‘fixed’, ‘prescribed’, ‘free’)
partition_size	AIC assembly partition size	1	N/A	int	[1, total panels]
iterative (WIP)	Flag to toggle GMRES iterative solver	False	N/A	bool	(False, True)
ROM	Flag to toggle ROMs	False	N/A	(string, bool)	(False, ‘ROM-POD’, ‘ROM-Krylov’ (WIP))
reuse_AIC	Flag to reuse AIC across evaluations	False	N/A	bool	(False, True)
ref_area	Reference area for coefficients	10.	m^2	scalar	N/A
ref_chord	Reference chord for coefficients	1.	m	scalar	N/A
moment_reference	Moment reference point	np.array([0., 0., 0.])	m	(3,)	N/A
drag_type	Method to compute drag	‘pressure’	N/A	string	(‘pressure’, ‘Trefftz’ (WIP))