gas.h File Reference

Gas properties for the compressible CFD codes. More...

#include "../../util/source/useful.h"

Go to the source code of this file.

Data Structures
struct	gas_data
	Thermodynamic state of the gas. More...
struct	ideal_gas_property_data
Defines
#define	PERF_AIR_14   0
#define	LOWT_AIR_14   1
#define	PERF_AIR_13   2
#define	PERF_HE_167   3
#define	EQ_AIR_1SP   4
#define	WEIRD_167   5
#define	PERF_AR_167   6
#define	EQ_N2   7
#define	PERF_N2   8
#define	EQ_CO2   9
#define	PERF_CO2   10
#define	PERF_HE_N2   11
#define	PERF_HE_AIR   12
#define	VIBEQ_N2   13
#define	VIBEQ_N2_HE   14
#define	PERF_AR_AIR   15
#define	IONIZE_AR_N2   16
#define	PERF_N2_LOWG   17
#define	NIT0   18
#define	NIT1   19
#define	NIT2   20
#define	PERF_R22_AIR   21
#define	PERF_GAS_MIX   22
#define	ARGON_POWERV   23
#define	PERF_NE_H2   24
#define	PERF_NE_H   25
#define	MULTI_T_GAS   26
#define	ARGON_LJ   27
#define	LUT_MIX   96
#define	LUTN   97
#define	LUT2   98
#define	LUT   99
#define	NSPECD   12
	Maximum number of species >= 0.
#define	NVIBD   3
	Maximum number of species that have separate vibrational energies.
#define	GAS_HEADER_ALREADY_INCLUDED
Typedefs
typedef int	eosfn (struct gas_data *, int, int)
Functions
int	copy_gas_data (struct gas_data *src, struct gas_data *dest)
	Make a complete copy of the gas data.
int	accumulate_gas_data (struct gas_data *src, struct gas_data *dest, double alpha)
	Accumulative copy of the gas data.
int	print_gas_data (struct gas_data *src)
	Print all gas_state data to stdout.
double *	copy_gas_data_to_buffer (struct gas_data *src, double *buf)
	Copy the abbreviated gas_data into a linear data buffer.
double *	copy_buffer_to_gas_data (struct gas_data *dest, double *buf)
	Copy the abbreviated gas_data from a linear data buffer.
int	number_of_values_in_gas_data_copy (void)
	Returns the number of double elements in each gas data copy.
int	set_ideal_gas_properties (int i, double R, double Gamma, double Prandtl, double Lewis, double mu_ref, double T_ref, double S)
int	set_type_of_gas (int gas_index)
	Selects the gas model.
eosfn *	get_EOS_function_pointer (void)
	Returns the pointer to the current equation of state function.
int	gas_type (void)
int	get_number_of_species (void)
int	get_number_of_vibrational_species (void)
int	separate_electron_energy (void)
double	gas_rhomin (void)
double	gas_pmin (void)
double	gas_amin (void)
double	gas_Tmin (void)
double	gas_Tmax (void)
gas_data *	new_gas_data_struct (void)
int	set_massf (struct gas_data *Q, int isp, double mf)
	Set the mass fraction for a particular species.
double	get_massf (struct gas_data *Q, int isp)
	Get the mass fraction for a particular species.
double	get_conc (struct gas_data *Q, int isp)
	Get the molar concentration for a particular species.
int	set_Tvib (struct gas_data *Q, int isp, double Tvib)
	Set the vibrational temperature for a particular species.
double	get_Tvib (struct gas_data *Q, int isp)
	Get the vibrational temperature for a particular species.
int	set_evib (struct gas_data *Q, int isp, double evib)
	Set the vibrational energy for a particular species.
double	get_evib (struct gas_data *Q, int isp)
	Get the vibrational energy for a particular species.
double	fill_in_concentrations (int first_sp, int last_sp, double rho, double *f, double *mol_w, double *c)
double	fill_in_mass_fractions (int first_sp, int last_sp, double rho, double *c, double *mol_w, double *f)
int	EOS_rhoe (struct gas_data *Q, int use_T_guess, int evaluate_visc_coeff)
	Evaluate thermodynamic state from given density and specific internal energy.
int	EOS_pT (struct gas_data *Q, int evaluate_visc_coeff)
	Compute the density, specific internal energy and local speed of sound from the pressure and temperature.
int	EOS_rhoT (struct gas_data *Q, int evaluate_visc_coeff)
	Compute the gas properties from given density and temperature.
int	EOS_rhop (struct gas_data *Q, int evaluate_visc_coeff)
	Compute the gas properties from given density and pressure.
double	dTdp_const_rho (struct gas_data *Q)
	Compute the derivative of temperature wrt pressure.
double	dTdrho_const_p (struct gas_data *Q)
	Compute the derivative of temperature wrt density.
int	eos_ideal_gas_one_species (struct gas_data *, int, int)
	Compute the pressure, temperature and local speed of sound from the density and the specific internal energy for a single-species ideal gas.
int	eos_weird_167 (struct gas_data *, int, int)
	A strange nitrogen model to match DSMC calculations.
int	eos_argon_power_law (struct gas_data *, int, int)
	An argon model with power-law viscosity to match DSMC calculations.
int	eos_argon_lennard_jones (struct gas_data *, int, int)
	An argon model with Lennard-Jones viscosity and constants fitted to Chapman and Cowling's figure 10.
int	eos_lut_one_species (struct gas_data *, int, int)
	A single-species gas using the look-up-table for properties.
int	eos_lut_n_species (struct gas_data *, int, int)
	Multiple-species mix where all properties come from a number of look-up-tables.
int	eos_equil_air_tannehill (struct gas_data *, int, int)
	Single-species mixture model for air.
int	eos_equil_n2_paj (struct gas_data *, int, int)
	Nitrogen in chemical equilibrium.
int	eos_equil_co2_iaj (struct gas_data *, int, int)
	Carbon-dioxide in chemical equilibrium.
int	eos_equil_vib_n2 (struct gas_data *, int, int)
	Nonreaction nitrogen but with vibrational energy in thermodynamic equilibrium.
int	eos_ideal_gas_binary_mix (struct gas_data *, int, int)
	Mix of two ideal gases.
int	eos_equil_vib_n2_he_mix (struct gas_data *, int, int)
	Mix of nitrogen (species 0) with equilibrium vibrational energy with ideal helium (species 1).
int	eos_ionize_ar_n2_mix (struct gas_data *, int, int)
	Mix of ideal nitrogen (species 0) with ionizing argon (species 1).
int	eos_lut_mix (struct gas_data *, int, int)
	Look-Up-Table for one species plus mix of perfect gases.
int	eos_null_function (struct gas_data *, int, int)
	Dummy function.

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Detailed Description

Gas properties for the compressible CFD codes.

Author:

PJ, 28-Sep-02

Version:

Separated from the main mb_cns code.

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Define Documentation

#define PERF_AIR_14   0

* The following are the available gas types... * * PERF_AIR_14 : Perfect gas, air, GAMMA = 1.4 * LOWT_AIR_14 : Low temperature air, GAMMA = 1.4, fudged Sutherland * constants. * PERF_AIR_13 : Perfect gas, air, GAMMA = 1.3 * PERF_HE_167 : Perfect gas, Helium, GAMMA = 1.667 * EQ_AIR_1SP : Equilibrium Air, 1-specie, Tannehill EOS * WEIRD_167 : Weird air with GAMMA = 1.667 to match the * DSMC satellite simulations * PERF_AR_167 : Perfect gas Argon with GAMMA = 1.667 * EQ_N2 : Nitrogen in chemical equilibrium (see n2eq.c) * PERF_N2 : Nitrogen -- perfect gas * EQ_CO2 : Carbon-dioxide in chemical equilibrium * PERF_CO2 : Carbon-dioxide -- perfect gas * PERF_HE_N2 : perfect gas mix of helium and nitrogen * PERF_HE_AIR : perfect gas mix of helium and air * VIBEQ_N2 : nitrogen molecules with vibrational equilibrium * VIBEQ_N2_HE : mix of helium with nitrogen in vib. equilibrium * PERF_AR_AIR : mix of argon and air (perfect gases) * IONIZE_AR_N2: mix of ionizing argon and inert nitrogen (vib eq) * PERF_N2_LOWG: perfect gas nitrogen with low GAMMA to simulate high T * NIT0,1,2 : three other nitrogen models for MNM * PERF_R22_AIR: perfect gas mix of R22 and air * PERF_GAS_MIX: perfect gas mix of species defined in "species.dat" * ARGON_POWERV: Argon with power-law viscosity for MNM * PERF_NE_H2 : perfect gas mix of neon atoms and hydrogen molecules * PERF_NE_H : perfect gas mix of neon atoms and hydrogen atoms * MULTI_T_GAS : Rowan's gas mixture with multiple temperatures * translational+vibrational+electrons * ARGON_LJ : Ideal argon with Lennard-Jones viscosity * * LUT : Look up table for thermodynamic and transport properties. * LUT2 : Two species gas with Look up tables for thermodynamic and * transport properties. * LUTN : Multiple-species gas with look-up tables. * LUT_MIX : LUT with ideal gas mix. See lut_mix(). *

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Function Documentation

int accumulate_gas_data (  struct gas_data *  src, struct gas_data *  dest, double  alpha )  [inline]

Accumulative copy of the gas data. Typically used in the CFD code to replace bad-cell data.

double* copy_buffer_to_gas_data (  struct gas_data *  dest, double *  buf )  [inline]

Copy the abbreviated gas_data from a linear data buffer. Parameters: dest,:  pointer to the gas_data structure buf  : pointer to the current element somewhere in buffer Returns: a pointer to the next available location in the data buffer.

int copy_gas_data (  struct gas_data *  src, struct gas_data *  dest )  [inline]

Make a complete copy of the gas data. Typically used in the CFD code to make ghost-cell copies.

double* copy_gas_data_to_buffer (  struct gas_data *  src, double *  buf )  [inline]

Copy the abbreviated gas_data into a linear data buffer. Parameters: src  : pointer to the gas_data structure buf  : pointer to the current element somewhere in buffer Returns: a pointer to the next available location in the data buffer.

double dTdp_const_rho (  struct gas_data *  Q  )

Compute the derivative of temperature wrt pressure. Parameters: Q  : pointer to the gas_data structure already containing desired pressure and density. Returns: : approximation to derivative. Note: The gas state properties may be mangled by this function.

double dTdrho_const_p (  struct gas_data *  Q  )

Compute the derivative of temperature wrt density. Parameters: Q  : pointer to the gas_data structure already containing desired pressure and density. Returns: : approximation to derivative. Note: The gas state properties may be mangled by this function.

int eos_ideal_gas_one_species (  struct gas_data *  Q, int  use_T_guess, int  evaluate_visc_coeff )

Compute the pressure, temperature and local speed of sound from the density and the specific internal energy for a single-species ideal gas. Parameters: Q  : pointer to the gas_data structure use_T_guess  : 0 : don't use Q.T as a guess for Temperature 1 : Q.T is available as an initial guess * Also, the following elements of the gas state are updated... * p : pressure in Pa * T : absolute temperature, degrees K * a : sound speed, m/s * * ...and, if the viscous_flag is set... * mu : molecular viscosity in Pa.s * lmbda : second viscosity coefficient, Pa.s * k : thermal conductivity coefficient * Returns: 0 if all is OK, 1 otherwise.

int eos_lut_mix (  struct gas_data *  Q, int  use_T_guess, int  evaluate_visc_coeff )

Look-Up-Table for one species plus mix of perfect gases. * The so-called-species are: * 0 LUT * 1 argon * 2 helium * 3 nitrogen * 4 air * This arrangement (of having LUT as species 0) allows us * to drop back to using the eos_lut_one_species() function * when the LUT gas is the only significant component. *

int eos_lut_n_species (  struct gas_data *  Q, int  use_T_guess, int  evaluate_visc_coeff )

Multiple-species mix where all properties come from a number of look-up-tables. Note that only one table at a time provides the gas-mix properties. This table is determined by the dominant species (as measured by mass fraction).

int eos_lut_one_species (  struct gas_data *  Q, int  use_T_guess, int  evaluate_visc_coeff )

A single-species gas using the look-up-table for properties. Note that a mix of gases in chemical equilibrium is handled by this model. Use the Chemical Equilibrium Analysis program from NASA Glenn to generate the table. The programs cea_driver.tcl and cea_to_binary.c are provided to automate the table generation process.

int EOS_pT (  struct gas_data *  Q, int  evaluate_visc_coeff )

Compute the density, specific internal energy and local speed of sound from the pressure and temperature. The process used is going to be a bit slow but this function is not intended for use within the inner loops of the simulation code. Parameters: Q  : pointer to the gas_data structure Returns: : a value of 0 if all is OK, 1 if something goes wrong.

int EOS_rhoe (  struct gas_data *  Q, int  use_T_guess, int  evaluate_visc_coeff )

Evaluate thermodynamic state from given density and specific internal energy. This is a convenience function so that we don't always have to deal with function pointers. The real work is delegated to the specialized EOS functions, one for each gas model. Parameters: Q  : pointer to the gas data structure use_T_guess  : ==1 use the given value of temparature as a starting guess, if necessary. evaluate_visc_coeff  : ==1 to invoke the calculation of the viscous transport coefficients Returns: 0 on success nonzero for failure

int EOS_rhop (  struct gas_data *  Q, int  evaluate_visc_coeff )

Compute the gas properties from given density and pressure. The process used is going to be a bit slow but this function is not intended for use within the inner loops of the simulation code. Parameters: Q  : pointer to the gas_data structure Returns: : a value of 0 if all is OK, 1 if something goes wrong.

int EOS_rhoT (  struct gas_data *  Q, int  evaluate_visc_coeff )

Compute the gas properties from given density and temperature. The process used is going to be a bit slow but this function is not intended for use within the inner loops of the simulation code. Parameters: Q  : pointer to the gas_data structure Returns: : a value of 0 if all is OK, 1 if something goes wrong.

double get_conc (  struct gas_data *  Q, int  isp )

Get the molar concentration for a particular species. This function is mainly to allow convenient access from the SWIG interface.

eosfn* get_EOS_function_pointer (  void   )  [inline]

Returns the pointer to the current equation of state function. The CFD functions can then invoke the appropriate EOS for the gas model.

double get_evib (  struct gas_data *  Q, int  isp )

Get the vibrational energy for a particular species. This function is mainly to allow convenient access from the SWIG interface.

double get_massf (  struct gas_data *  Q, int  isp )

Get the mass fraction for a particular species. This function is mainly to allow convenient access from the SWIG interface.

double get_Tvib (  struct gas_data *  Q, int  isp )

Get the vibrational temperature for a particular species. This function is mainly to allow convenient access from the SWIG interface.

int number_of_values_in_gas_data_copy (  void   )  [inline]

Returns the number of double elements in each gas data copy. We need this to work out where we should be in the buffer for each copy.

int set_evib (  struct gas_data *  Q, int  isp, double  evib )

Set the vibrational energy for a particular species. This function is mainly to allow convenient access from the SWIG interface.

int set_massf (  struct gas_data *  Q, int  isp, double  mf )

Set the mass fraction for a particular species. This function is mainly to allow convenient access from the SWIG interface.

int set_Tvib (  struct gas_data *  Q, int  isp, double  Tvib )

Set the vibrational temperature for a particular species. This function is mainly to allow convenient access from the SWIG interface.

int set_type_of_gas (  int  gas_index  )

Selects the gas model. This is done by setting the gas model equation-of-state pointer and a few other gas-model specific constants. Parameters: gas_index,:  look up gas.h to see the allowable values.

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