#*------------------------------------------------------------------------------*
#* JAX-FLUIDS - *
#* *
#* A fully-differentiable CFD solver for compressible two-phase flows. *
#* Copyright (C) 2022 Deniz A. Bezgin, Aaron B. Buhendwa, Nikolaus A. Adams *
#* *
#* This program is free software: you can redistribute it and/or modify *
#* it under the terms of the GNU General Public License as published by *
#* the Free Software Foundation, either version 3 of the License, or *
#* (at your option) any later version. *
#* *
#* This program is distributed in the hope that it will be useful, *
#* but WITHOUT ANY WARRANTY; without even the implied warranty of *
#* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
#* GNU General Public License for more details. *
#* *
#* You should have received a copy of the GNU General Public License *
#* along with this program. If not, see <https://www.gnu.org/licenses/>. *
#* *
#*------------------------------------------------------------------------------*
#* *
#* CONTACT *
#* *
#* deniz.bezgin@tum.de // aaron.buhendwa@tum.de // nikolaus.adams@tum.de *
#* *
#*------------------------------------------------------------------------------*
#* *
#* Munich, April 15th, 2022 *
#* *
#*------------------------------------------------------------------------------*
from typing import List, Union
import types
import jax.numpy as jnp
from jaxfluids.materials.material import Material
from jaxfluids.unit_handler import UnitHandler
[docs]
class SafeIdealGas(Material):
"""Implements the safe ideal gas law, i.e., prevents division by zero and negative square roots"""
def __init__(self, unit_handler: UnitHandler, dynamic_viscosity: Union[float, str, types.LambdaType], sutherland_parameters: List,
bulk_viscosity: float, thermal_conductivity: Union[float, str, types.LambdaType], prandtl_number: float,
specific_heat_ratio: float, specific_gas_constant: float, **kwargs) -> None:
super().__init__(unit_handler, dynamic_viscosity, sutherland_parameters, bulk_viscosity, thermal_conductivity, prandtl_number)
self.gamma = specific_heat_ratio
self.R = unit_handler.non_dimensionalize(specific_gas_constant, "specific_gas_constant")
self.cp = self.gamma / (self.gamma - 1) * self.R
[docs]
def get_psi(self, p, rho):
"""See base class. """
return jnp.maximum( p, self.eps) / rho
[docs]
def get_grueneisen(self, rho):
"""See base class. """
return self.gamma - 1
[docs]
def get_speed_of_sound(self, p: jnp.ndarray, rho: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
return jnp.sqrt( self.gamma * jnp.maximum( p, self.eps) / jnp.maximum( rho, self.eps ) )
[docs]
def get_pressure(self, e: jnp.ndarray, rho: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
return (self.gamma - 1) * e * rho
[docs]
def get_temperature(self, p: jnp.ndarray, rho: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
return p / ( rho * self.R + self.eps )
[docs]
def get_energy(self, p: jnp.ndarray, rho: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
return jnp.maximum( p, self.eps) / jnp.maximum( rho, self.eps ) / (self.gamma - 1)
[docs]
def get_total_energy(self, p: jnp.ndarray, rho: jnp.ndarray, u: jnp.ndarray, v: jnp.ndarray, w: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
# Total energy per unit volume
return jnp.maximum( p, self.eps) / (self.gamma - 1) + 0.5 * jnp.maximum( rho, self.eps) * ( (u * u + v * v + w * w) )
[docs]
def get_total_enthalpy(self, p: jnp.ndarray, rho: jnp.ndarray, u: jnp.ndarray, v: jnp.ndarray, w: jnp.ndarray) -> jnp.ndarray:
"""See base class. """
# Total specific enthalpy
return (self.get_total_energy(p, rho, u, v, w) + jnp.maximum( p, self.eps)) / jnp.maximum( rho, self.eps)