7.6.17.48.5. Mmp_Model

Syntax: Specific Surface Area [{of} SpeciesName] = Mmp_Model Rho_C_Init = rho_c_init
Scope: Aria Material
Summary: Computes the specific surface area based on the micromechanics pressurization model
Description: Computes the specific surface area (SSA) pore damage metric via the MMP model. This is computed as $SSA =\frac{3/(r)}{\rho_{pg} +\left(\frac{\rho_{co}}{1+\varepsilon_T}\right)\left( \phi^{-1} - 1\right) }$ . Here, $r$ is the PORE DEFECT RADIUS, $\rho_{pg}$ is the PORE GAS DENSITY, $\rho_{co}$ is the initial condensed density, $\varepsilon_{T}$ is the thermal strain (computed from the PORE DEFECT RADIUS model), and $\phi$ is the gas volume fraction.