real_T *P, real_T *T, real_T x[12])

{

real_T y;

int32_T i;

real_T MW;

real_T dT;

static const real_T b[12] = { 1.00794, 15.9994, 14.0067, 2.01588, 17.00734,

28.0101, 30.0061, 31.9988, 18.01528, 44.0095, 28.0134, 39.948 };

real_T R;

real_T T_err;

real_T T_qt;

real_T a_CO2[7];

real_T a_CO[7];

real_T a_O2[7];

real_T a_H2[7];

real_T a_H2O[7];

real_T a_OH[7];

real_T a_O[7];

real_T a_N2[7];

real_T a_N[7];

real_T a_NO[7];

static const real_T dv32[7] = { 4.6365111, 0.0027414569, -9.9589759E-7,

1.6038666E-10, -9.1619857E-15, -49024.904, -1.9348955 };

static const real_T dv33[7] = { 3.0484859, 0.0013517281, -4.8579405E-7,

7.8853644E-11, -4.6980746E-15, -14266.117, 6.0170977 };

static const real_T dv34[7] = { 3.66096083, 0.000656365523, -1.41149485E-7,

2.05797658E-11, -1.29913248E-15, -1215.97725, 3.41536184 };

static const real_T dv35[7] = { 2.9328305, 0.00082659802, -1.4640057E-7,

1.5409851E-11, -6.8879615E-16, -813.05582, -1.0243164 };

static const real_T dv36[7] = { 2.6770389, 0.0029731816, -7.7376889E-7,

9.4433514E-11, -4.2689991E-15, -29885.894, 6.88255 };

static const real_T dv37[7] = { 2.83853033, 0.00110741289, -2.94000209E-7,

4.20698729E-11, -2.4228989E-15, 3697.80808, 5.84494652 };

static const real_T dv38[7] = { 2.54363697, -2.73162486E-5, -4.1902952E-9,

4.95481845E-12, -4.79553694E-16, 29226.012, 4.92229457 };

static const real_T dv39[7] = { 2.95257637, 0.0013969004, -4.92631603E-7,

7.86010195E-11, -4.60755204E-15, -923.948688, 5.87188762 };

static const real_T dv40[7] = { 2.4159429, 0.00017489065, -1.1902369E-7,

3.0226244E-11, -2.0360983E-15, 56133.775, 4.6496095 };

static const real_T dv41[7] = { 3.26071234, 0.00119101135, -4.29122646E-7,

6.94481463E-11, -4.03295681E-15, 9921.43132, 6.36900518 };

static const real_T dv42[7] = { 2.356813, 0.0089841299, -7.1220632E-6,

2.4573008E-9, -1.4288548E-13, -48371.971, 9.9009035 };

static const real_T dv43[7] = { 3.5795335, -0.00061035369, 1.0168143E-6,

9.0700586E-10, -9.0442449E-13, -14344.086, 3.5084093 };

static const real_T dv44[7] = { 3.78245636, -0.00299673415, 9.847302E-6,

-9.68129508E-9, 3.24372836E-12, -1063.94356, 3.65767573 };

static const real_T dv45[7] = { 2.3443029, 0.0079804248, -1.9477917E-5,

2.0156967E-8, -7.3760289E-12, -917.92413, 0.68300218 };

static const real_T dv46[7] = { 4.1986352, -0.0020364017, 6.5203416E-6,

-5.4879269E-9, 1.771968E-12, -30293.726, -0.84900901 };

static const real_T dv47[7] = { 3.99198424, -0.00240106655, 4.61664033E-6,

-3.87916306E-9, 1.36319502E-12, 3368.89836, -0.103998477 };

static const real_T dv48[7] = { 3.1682671, -0.00327931884, 6.64306396E-6,

-6.12806624E-9, 2.11265971E-12, 29122.2592, 2.05193346 };

static const real_T dv49[7] = { 3.53100528, -0.000123660988, -5.02999433E-7,

2.43530612E-9, -1.40881235E-12, -1046.97628, 2.96747038 };

static const real_T dv50[7] = { 2.5, 0.0, 0.0, 0.0, 0.0, 56104.638, 4.1939088

};

static const real_T dv51[7] = { 4.21859896, -0.00463988124, 1.10443049E-5,

-9.34055507E-9, 2.80554874E-12, 9845.09964, 2.28061001 };

real_T a_H[84];

static const real_T b_a_H[7] = { 2.5, 0.0, 0.0, 0.0, 0.0, 25473.66,

-0.44668285 };

static const real_T a_Ar[7] = { 2.5, 0.0, 0.0, 0.0, 0.0, -745.375, 4.3796749 };

real_T a_gas[7];

int32_T i6;

real_T T_arr_Cp[7];

real_T T_arr_h[7];

static const real_T dv52[12] = { 26219.035, 29968.7009, 56850.013, 0.0,

4486.1538, -13293.628, 10977.0882, 0.0, -29084.817, -47328.105, 0.0, 0.0 };

static const int32_T iv1[12] = { -6197000, -6725000, -6197000, -8467000,

-9172000, -8671000, -9192000, -8683000, -9904000, -9364000, -8670000,

-6197000 };

real_T b_y;

/* Calculate the pressure, temperature and composition of the combustion gas */

/* from given internal energy, volume and mass of each gas specie. */

/* */

/* The calculation of the internal energy is based on the NASA 7 */

/* coefficient polynomial and T is found by using Newton-Raphson method. */

/* The gas is assumed to be idea gas. */

/* */

/* Input */

/* N : No. moles of each gas specie (kmol) */

/* N(1) = N_H; N(2) = N_O; N(3) = N_N; N(4) = N_H2; */

/* N(5) = N_OH; N(6) = N_CO; N(7) = N_NO; N(8) = N_O2; */

/* N(9) = N_H2O; N(10) = N_CO2;N(11) = N_N2; N(12) = N_Ar */

/* E : Internal energy of the gas */

/* V : Volume of the gas */

/* Output */

/* P : Pressure (Pa) */

/* T : Temperature (K) */

/* rho : Density (kg/m3) */

/* x : Mole fraction of each gas specie */

/* x(1) = x_H; x(2) = x_O; x(3) = x_N; x(4) = x_H2; x(5) = x_OH; */

/* x(6) = x_CO; x(7) = x_NO; x(8) = x_O2; x(9) = x_H2O; x(10) = x_CO2; */

/* x(11) = x_N2; x(12) = x_Ar */

/* */

/* Atomic weight calculation from NIST atomic weights */

/* Ref : http://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl */

/* */

/* The NASA 7-coefficients are obtained from the reference: */

/* Burcat, A., B. Ruscic, et al. (2005). Third millenium ideal gas and */

/* condensed phase thermochemical database for combustion with updates */

/* from active thermochemical tables, Argonne National Laboratory */

/* Argonne, IL. */

/* */

/* Created by Kevin Koosup Yum on 29 June */

/* % */

/* in J/kmol/K */

/* % Calculate the composition in mole fraction and gas constant */

y = N[0];

for (i = 0; i < 11; i++) {

y += N[i + 1];

}

MW = 0.0;

for (i = 0; i < 12; i++) {

dT = N[i] / y;

MW += dT * b[i];

x[i] = dT;

}

/* in kg/kmol */

R = 8314.4621 / MW;

/* in J/kg/K */

/* % Calculate the temperature */

*T = T_prev;

dT = 0.0;

T_err = 1.0;

while (T_err > 0.001) {

*T -= dT;

dT = *T * *T;

T_err = rt_powd_snf(*T, 3.0);

T_qt = rt_powd_snf(*T, 4.0);

if (*T >= 1000.0) {

/* Valid upto */

for (i = 0; i < 7; i++) {

a_CO2[i] = dv32[i];

/* 1000~6000K */

a_CO[i] = dv33[i];

/* 1000~6000K */

a_O2[i] = dv34[i];

/* 1000~6000K */

a_H2[i] = dv35[i];

/* 1000~6000K */

a_H2O[i] = dv36[i];

/* 1000~6000K */

a_OH[i] = dv37[i];

/* 1000~6000K */

/* 1000~6000K */

a_O[i] = dv38[i];

/* 1000~6000K */

a_N2[i] = dv39[i];

/* 1000~6000K */

a_N[i] = dv40[i];

/* 1000~6000K */

a_NO[i] = dv41[i];

}

/* 1000~6000K */

} else {

for (i = 0; i < 7; i++) {

a_CO2[i] = dv42[i];

/* 300~1000K */

a_CO[i] = dv43[i];

/* 300~1000K */

a_O2[i] = dv44[i];

/* 300~1000K */

a_H2[i] = dv45[i];

/* 300~1000K */

a_H2O[i] = dv46[i];

/* 300~1000K */

a_OH[i] = dv47[i];

/* 300~1000K */

/* 300~1000K */

a_O[i] = dv48[i];

/* 300~1000K */

a_N2[i] = dv49[i];

/* 300~1000K */

a_N[i] = dv50[i];

/* 300~1000K */

a_NO[i] = dv51[i];

}

/* 300~1000K */

}

for (i = 0; i < 7; i++) {

a_H[12 * i] = b_a_H[i];

a_H[1 + 12 * i] = a_O[i];

a_H[2 + 12 * i] = a_N[i];

a_H[3 + 12 * i] = a_H2[i];

a_H[4 + 12 * i] = a_OH[i];

a_H[5 + 12 * i] = a_CO[i];

a_H[6 + 12 * i] = a_NO[i];

a_H[7 + 12 * i] = a_O2[i];

a_H[8 + 12 * i] = a_H2O[i];

a_H[9 + 12 * i] = a_CO2[i];

a_H[10 + 12 * i] = a_N2[i];

a_H[11 + 12 * i] = a_Ar[i];

a_gas[i] = 0.0;

for (i6 = 0; i6 < 12; i6++) {

a_gas[i] += x[i6] * a_H[i6 + 12 * i];

}

}

T_arr_Cp[0] = 1.0;

T_arr_Cp[1] = *T;

T_arr_Cp[2] = dT;

T_arr_Cp[3] = T_err;

T_arr_Cp[4] = T_qt;

T_arr_Cp[5] = 0.0;

T_arr_Cp[6] = 0.0;

T_arr_h[0] = 1.0;

T_arr_h[1] = *T / 2.0;

T_arr_h[2] = dT / 3.0;

T_arr_h[3] = T_err / 4.0;

T_arr_h[4] = T_qt / 5.0;

T_arr_h[5] = 1.0 / *T;

T_arr_h[6] = 0.0;

/* (J/kmol / J/kmol/K) */

/* J/kmol */

y = 0.0;

dT = 0.0;

for (i = 0; i < 12; i++) {

y += dv52[i] * x[i];

dT += (real_T)iv1[i] * x[i];

}

T_err = R * *T;

T_qt = 0.0;

b_y = 0.0;

for (i = 0; i < 7; i++) {

T_qt += T_err * a_gas[i] * T_arr_h[i];

b_y += a_gas[i] * T_arr_Cp[i];

}

dT = (((T_qt - (R * y + dT / MW)) - R * *T) - E / m) / (R * (b_y - 1.0));

T_err = fabs(dT) / *T;

}

/* % Calculate the pressure */

*P = m / V * R * *T;