def RiemFluid_TP(T, P, *, fluid):
from ctREFPROP.ctREFPROP import REFPROPFunctionLibrary
PATH = r'D:\REFPROP'
RP = REFPROPFunctionLibrary(PATH)
MOLAR_BASE_SI = RP.GETENUMdll(0, 'MOLAR BASE SI').iEnum
RP.SETPATHdll(PATH)
RP.SETFLUIDSdll(fluid)
rhomolar, Riem = RP.REFPROPdll('', 'TP', 'D;RIEM', MOLAR_BASE_SI, 0, 0, T,
P, [1.0]).Output[0:2]
rhoN = rhomolar * N_A
z = [1.0] + [0.0] * 19
Ar00, Ar01, Ar10, Ar02, Ar11, Ar20, Ar03, Ar12, Ar21, Ar30 = RP.REFPROPdll(
'', 'TD',
'PHIR00;PHIR01;PHIR10;PHIR02;PHIR11;PHIR20;PHIR03;PHIR12;PHIR21;PHIR30',
MOLAR_BASE_SI, 0, 0, T, rhomolar, z).Output[0:10]
Ao00, Ao01, Ao10, Ao02, Ao11, Ao20, Ao03, Ao12, Ao21, Ao30 = RP.REFPROPdll(
'', 'TD',
'PHIG00;PHIG01;PHIG10;PHIG02;PHIG11;PHIG20;PHIG03;PHIG12;PHIG21;PHIG30',
MOLAR_BASE_SI, 0, 0, T, rhomolar, z).Output[0:10]
Bstar = 1 + 2 * Ar01 + Ar02
cvstar = -Ao20 - Ar20
# First derivatives
TdBdT = -(2 * Ar11 + Ar12)
TdcvdT = ((2 * Ao20 + Ao30) + (2 * Ar20 + Ar30))
rhodBdrho = (2 * (Ar01 + Ar02) + (2 * Ar02 + Ar03))
rhodcvdrho = -Ar21
# Combinations of first derivatives
rhodlnBcvdrho = 1 / Bstar * rhodBdrho + 1 / cvstar * rhodcvdrho
TdlnBcvdT = 1 / Bstar * TdBdT + 1 / cvstar * TdcvdT
rhodlnBovercvdrho = 1 / Bstar * rhodBdrho - 1 / cvstar * rhodcvdrho
# Second derivatives, same treatment as first derivatives,
# Fourth derivatives cancel conveniently
T2dBdT2_plus_rho2dcvdrho2 = (4 * Ar11 + 2 * Ar12 + 2 * Ar21)
Rstar = 1 / (Bstar * cvstar) * (TdBdT *
(1 - 0.5 * TdlnBcvdT) + rhodcvdrho *
(1 - 0.5 * rhodlnBcvdrho) -
0.5 * cvstar * rhodlnBovercvdrho +
T2dBdT2_plus_rho2dcvdrho2)
here = Rstar / rhoN # [m^3]
return here * 1e27, Riem # [nm^3]
def time_REFPROP(n, Nrep):
root = os.environ['RPPREFIX']
RP = REFPROPFunctionLibrary(root)
RP.SETFLUIDSdll('METHANE')
if n == 0:
f = lambda D, T: RP.REFPROP1dll(D, T)
elif n == 1:
f = lambda AS: AS.delta() * AS.dalphar_dDelta()
elif n == 2:
f = lambda AS: AS.delta()**2 * AS.d2alphar_dDelta2()
elif n == 3:
f = lambda AS: AS.delta()**3 * AS.d3alphar_dDelta3()
else:
raise ValueError(n)
T = 300
rho = 3.0
z = [1.0]
tic = timeit.default_timer()
for i in range(Nrep):
RP.PRESSdll(T, rho / 1e3, z)
toc = timeit.default_timer()
elap = (toc - tic) / Nrep
return elap