Numerical simulation of cooling of a heat-releasing porous layer submerged in water is carried out. Using the analytical and numerical models, the critical conditions under which local dryout of the porous medium occurs are studied. Numerical and analytical solutions obtained with different drag models, including those which explicitly account for the interphase drag, are analyzed. The uncertainty factors affecting the dryout heat flux are considered. Global sensitivity analysis is applied to the dryout heat flux as a function of physical and model parameters. Optimization of model parameters determining the functional dependencies of the relative phase permeability is carried out versus the experimental data available. Sensitivity indices are obtained for the dryout heat flux dependence on the physical parameters of the problem (particle diameter, porosity, system pressure). Probability density functions are obtained for the dryout heat flux, and the boundaries of the safe zone in which steady-state cooling of the porous layer is possible without local dryout are constructed.
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