Comparison of the algorithms PISO and simpler for solving pressure-velocity linked equations in simulating compartmental fire

This article reports a comparison of three algorithms SIMPLER, PISO, and iterative PISO, for solving pressure-velocity linked equations in simulating fire using the field modeling technique. The set of equations describing transient three-dimensional turbulent fluid flow induced by a fire was solved. The standard k-epsilon turbulent model is employed for describing the turbulent effect. Numerical experiments were performed in simulating the fire-induced flow and temperature in the large test room reported by Ingason and Olsson [15]. The predicted results using the three algorithms are compared with the experimental data. The results show that the iterative-type solution method is good for fire field modeling. Solutions predicted from the original noniterative PISO algorithm might not satisfy the continuity equation, but do give preliminary estimation for fire engineering application, as the required computation time is significantly reduced. The treatment of free boundary conditions for the cases studied are important in achieving a reasonably steady state solution.