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defining a term for a domain using DEFINE_ADJUST |
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September 22, 2010, 00:23 |
defining a term for a domain using DEFINE_ADJUST
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#1 |
Senior Member
MASOUD
Join Date: Mar 2009
Posts: 102
Rep Power: 17 |
Hi,
My geometry is including 5 subdomains (it's a fuel cell). I'd like to define different reaction rate in different zones. I guess DEFINE_ADJUST could be a good idea. How can I do this? Here is the code: ***************** #include "udf.h" #include "sg.h" /* Define which user-defined scalars to use. */ enum { E_CHARGE_UDS, C_CHARGE_UDS, N_REQUIRED_UDS }; static real ACT_AREA_A=270; static real ACT_AREA_C=300; static real REF_EXCH_CURR_A=2.1; static real REF_EXCH_CURR_C=0.40; static real REV_POT=1.02; static real MW_H2=0.032; static real MW_H2O=0.032; static real MW_O2=0.032; static real MW_CO2=0.044; static real MW_N2=0.032; static real MW_MIX; static real X_H2; static real X_H2O; static real X_O2; static real X_CO2; static real X_N2; static real ALPHA_A=1.5; static real ALPHA_C=0.5; static real NO_ELEC=2; static real FARADAY=96485; static real UNI_GAS_CONS=8.314; static real STOCH_H2=-1; static real STOCH_H2O=1; static real STOCH_O2=-0.5; static real STOCH_CO2_A=1; static real STOCH_CO2_C=-1; static real RXN_RATE_A; static real RXN_RATE_C; static real Z_A; static real ZZ_A; static real ZZZ_A; static real Z_C; static real ZZ_C; static real ZZZ_C; static real source; static real u=0.0; static real domain_ID=30; DEFINE_ADJUST(SUR,d) { u+=0.001; } DEFINE_ADJUST(UDM,d) { Thread *t; cell_t c; MW_MIX=MW_H2*C_YI(c,t,0)+MW_O2*C_YI(c,t,1)+MW_CO2* C_YI(c,t,2)+MW_H2O*C_YI(c,t,3)+MW_N2*C_YI(c,t,4); X_H2=C_YI(c,t,0)*MW_H2/MW_MIX; X_O2=C_YI(c,t,1)*MW_O2/MW_MIX; X_CO2=C_YI(c,t,2)*MW_CO2/MW_MIX; X_H2O=C_YI(c,t,3)*MW_H2O/MW_MIX; X_N2=C_YI(c,t,4)*MW_N2/MW_MIX; Z_A=ACT_AREA_A*REF_EXCH_CURR_A*(pow((X_H2),0.25)); ZZ_A=exp((ALPHA_A*FARADAY*(C_UDSI(c,t,0)-C_UDSI(c,t,1)))/(UNI_GAS_CONS*C_T(c,t))); ZZZ_A=exp(-(ALPHA_C*FARADAY*(C_UDSI(c,t,0)-C_UDSI(c,t,1)))/(UNI_GAS_CONS*C_T(c,t))); RXN_RATE_A=Z_A*(ZZ_A-ZZZ_A); C_UDMI(c,t,0)=RXN_RATE_A; Z_C=ACT_AREA_C*REF_EXCH_CURR_C*pow(X_O2,0.375)*pow (X_CO2,(-1.25)); ZZ_C=exp((ALPHA_A*FARADAY*(-(C_UDSI(c,t,0)-C_UDSI(c,t,1)-REV_POT)))/(UNI_GAS_CONS*C_T(c,t))); ZZZ_C=exp(-(ALPHA_C*FARADAY*(-(C_UDSI(c,t,0)-C_UDSI(c,t,1)-REV_POT)))/(UNI_GAS_CONS*C_T(c,t))); RXN_RATE_C=Z_C*(ZZ_C-ZZZ_C); C_UDMI(c,t,1)=RXN_RATE_C; } |
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September 24, 2010, 06:08 |
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#2 |
Member
Byron Smith R J
Join Date: Mar 2009
Location: India
Posts: 46
Rep Power: 17 |
use the macro get domain() where the domain numbe can be had from the boundary conditions and for each domain write the rate equation
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