User-Defined Property Optimization
The parameters for physical property, kinetic property, and user-defined property can also be optimized with respect to experimental data just like the parameters in a thermodynamic database. User can refer to Section User-Defined Properties for the format to define user-defined property in a database. Similar to the optimization of thermodynamic model parameters, user needs to define the parameters to be optimized in the database and prepare a pop file with corresponding experimental data. An example for the parameter definition in the database is shown below:
$Thermal conductivity of pure element in the Fcc phase
PARAMETER ThCond(Fcc,Al;0) 298.15 +311.72511-0.09661*T-13510.26/T; 3000 N !
PARAMETER ThCond(Fcc,Cu;0) 298.15 +417.28065-0.06598*T+944.065/T; 3000 N !
$Thermal conductivity interaction parameters for Fcc phase to be optimized
OPTIMIZATION Fcc_TC 0 0; 60000 N !
OPTIMIZATION Fcc_TCT -50 -24.6; 0 N !
OPTIMIZATION Fcc_TC_1 -60000 0; 0 N !
OPTIMIZATION Fcc_TCT_1 0 28; 50 N !
PARAMETER ThCond(Fcc,Al,Cu;0) 298.15 +Fcc_TC+Fcc_TCT*T; 3000 N !
PARAMETER ThCond(Fcc,Al,Cu;1) 298.15 +Fcc_TC_1+Fcc_TCT_1*T; 3000 N !
And an example pop file for the experimental data is shown below.
$Thermal Conductivity of the Fcc phase at 1000K
TABLE_HEAD
CREATE_NEW_EQUILIBRIUM @@,1
CHANGE_STATUS PHASE * = S
CHANGE_STATUS PHASE Fcc = FIX 1
SET_CONDITION T=1000, P = P0, X(Fcc,Cu) = @1
EXPERIMENT ThCond(Fcc)= @3 : @4
TABLE_VALUES
$ x(Cu) x(Al) TC DTC
0.05 0.95 194 50
0.1 0.9 295 50
0.2 0.8 750 50
0.8 0.2 3116 50
0.9 0.1 2122 50
0.95 0.05 1343 50
TABLE_END
The optimization procedure is the same as that for thermodynamic parameters. User may refer to the previous section for details and get the optimization result step by step.