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Fixed mixture derivative tests - all pass now

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Signed-off-by: Ian Bell <ian.h.bell@gmail.com>
This commit is contained in:
Ian Bell
2014-09-08 21:49:29 +02:00
parent 472643db4d
commit 494c27fa8b
1 changed files with 31 additions and 5 deletions
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36
src/Backends/Helmholtz/MixtureDerivatives.cpp
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@@ -489,7 +489,7 @@ TEST_CASE("Mixture derivative checks", "[mixtures],[mixture_derivs]")
double numeric = (v1 - v2)/(2*dT);
double err = std::abs((numeric-analytic)/analytic);
CHECK(err < 1e-8);
CHECK(err < 1e-6);
}
std::ostringstream ss3;
@@ -642,8 +642,21 @@ TEST_CASE("Mixture derivative checks", "[mixtures],[mixture_derivs]")
{
if (i == z.size()-1){break;}
double analytic = MixtureDerivatives::dalphar_dxi(rHEOS, i, xN_flag);
double v1 = rHEOS_pluszi.alphar();
double v2 = rHEOS_minuszi.alphar();
shared_ptr<HelmholtzEOSMixtureBackend> plus(new HelmholtzEOSMixtureBackend(names));
plus->specify_phase(iphase_gas);
plus->set_mole_fractions(zp);
plus->calc_reducing_state();
SimpleState red = plus->get_reducing_state();
plus->update(DmolarT_INPUTS, red.rhomolar*rHEOS.delta(), red.T/rHEOS.tau());
double v1 = plus->alphar();
shared_ptr<HelmholtzEOSMixtureBackend> minus(new HelmholtzEOSMixtureBackend(names));
minus->specify_phase(iphase_gas);
minus->set_mole_fractions(zm);
minus->calc_reducing_state();
red = minus->get_reducing_state();
minus->update(DmolarT_INPUTS, red.rhomolar*rHEOS.delta(), red.T/rHEOS.tau());
double v2 = minus->alphar();
double numeric = (v1 - v2)/(2*dz);
double err = std::abs((numeric-analytic)/analytic);
CAPTURE(numeric);
@@ -733,8 +746,21 @@ TEST_CASE("Mixture derivative checks", "[mixtures],[mixture_derivs]")
{
if (j == z.size()-1){break;}
double analytic = MixtureDerivatives::d2alphardxidxj(rHEOS,i,j,xN_flag);
double v1 = MixtureDerivatives::dalphar_dxi(rHEOS_pluszj, i, xN_flag);
double v2 = MixtureDerivatives::dalphar_dxi(rHEOS_minuszj, i, xN_flag);
shared_ptr<HelmholtzEOSMixtureBackend> plus(new HelmholtzEOSMixtureBackend(names));
plus->specify_phase(iphase_gas);
plus->set_mole_fractions(zp);
plus->calc_reducing_state();
SimpleState red = plus->get_reducing_state();
plus->update(DmolarT_INPUTS, red.rhomolar*rHEOS.delta(), red.T/rHEOS.tau());
double v1 = MixtureDerivatives::dalphar_dxi(*(plus.get()), i, xN_flag);
shared_ptr<HelmholtzEOSMixtureBackend> minus(new HelmholtzEOSMixtureBackend(names));
minus->specify_phase(iphase_gas);
minus->set_mole_fractions(zm);
minus->calc_reducing_state();
red = minus->get_reducing_state();
minus->update(DmolarT_INPUTS, red.rhomolar*rHEOS.delta(), red.T/rHEOS.tau());
double v2 = MixtureDerivatives::dalphar_dxi(*(minus.get()), i, xN_flag);
double numeric = (v1 - v2)/(2*dz);
double err = std::abs((numeric-analytic)/analytic);
if (std::abs(numeric) < DBL_EPSILON && std::abs(analytic) < DBL_EPSILON){break;}