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Fixed Helmholtz derivatives

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Ian Bell
2015-04-26 13:06:57 -06:00
parent 10f9d8cc8b
commit da0d318d6b
1 changed files with 17 additions and 4 deletions
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21
src/Helmholtz.cpp
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@@ -322,10 +322,17 @@ void ResidualHelmholtzNonAnalytic::all(const CoolPropDbl &tau, const CoolPropDbl
const CoolPropDbl theta = (1.0-tau)+Ai*pow(POW2(delta-1.0), 1.0/(2.0*betai));
const CoolPropDbl dtheta_dTau = -1;
const CoolPropDbl dtheta_dDelta = Ai/(betai)*pow(POW2(delta-1), 1/(2*betai)-1)*(delta-1);
const CoolPropDbl d2theta_dDelta2 = Ai/betai*(1/betai-1)*pow(POW2(delta-1), 1/(2*betai)-1);
const CoolPropDbl d3theta_dDelta3 = Ai/betai*(2-3/betai+1/POW2(betai))*pow(POW2(delta-1), 1/(2*betai)-1.5);
const CoolPropDbl d4theta_dDelta4 = Ai/betai*(-6+11/betai-6/POW2(betai)+1/POW3(betai))*pow(POW2(delta-1), 1/(2*betai)-2);
const CoolPropDbl d2theta_dDelta2 = Ai/betai*(1/betai-1)*pow(POW2(delta-1), 1/(2*betai)-1);
CoolPropDbl d3theta_dDelta3;
if (std::abs(delta-1) < DBL_EPSILON){
d3theta_dDelta3 = Ai/betai*(2-3/betai+1/POW2(betai))*pow(POW2(delta-1), 1/(2*betai)-1.5);
}
else{
d3theta_dDelta3 = Ai/betai*(2-3/betai+1/POW2(betai))*pow(POW2(delta-1), 1/(2*betai))/POW3(delta-1);
}
const CoolPropDbl d4theta_dDelta4 = Ai/betai*(-6+11/betai-6/POW2(betai)+1/POW3(betai))*pow(POW2(delta-1), 1/(2*betai)-2);
// Derivatives of PSI (OK - checked)
const CoolPropDbl PSI = exp(-Ci*POW2(delta-1.0)-Di*POW2(tau-1.0));
const CoolPropDbl dPSI_dDelta_over_PSI = -2.0*Ci*(delta-1.0);
@@ -358,7 +365,13 @@ void ResidualHelmholtzNonAnalytic::all(const CoolPropDbl &tau, const CoolPropDbl
const CoolPropDbl d3DELTA_dTau3 = 0;
const CoolPropDbl d3DELTA_dDelta_dTau2 = 0;
const CoolPropDbl d3DELTA_dDelta2_dTau = 2*dtheta_dTau*d2theta_dDelta2;
const CoolPropDbl d3DELTA_dDelta3 = 2*(theta*d3theta_dDelta3 + 3*dtheta_dDelta*d2theta_dDelta2 + 2*Bi*ai*(2*ai*ai - 3*ai + 1)*pow(POW2(delta-1.0), ai -1.0 -0.5));
CoolPropDbl d3DELTA_dDelta3;
if (std::abs(delta-1) < DBL_EPSILON){
d3DELTA_dDelta3 = 2*(theta*d3theta_dDelta3 + 3*dtheta_dDelta*d2theta_dDelta2 + 2*Bi*ai*(2*ai*ai - 3*ai + 1)*pow(POW2(delta-1.0), ai -1.0 - 0.5));
}
else{
d3DELTA_dDelta3 = 2*(theta*d3theta_dDelta3 + 3*dtheta_dDelta*d2theta_dDelta2 + 2*Bi*ai*(2*ai*ai - 3*ai + 1)*pow(POW2(delta-1.0), ai-1.0)/(delta-1));
}
const CoolPropDbl d4DELTA_dTau4 = 0;
const CoolPropDbl d4DELTA_dDelta_dTau3 = 0;
const CoolPropDbl d4DELTA_dDelta2_dTau2 = 0;