Unsteady heat transfer analysis of an impinging jet with high-order spectral element methods

Numerical simulations are a powerful tool to understand the kinematic and thermodynamic behaviour of impinging jet, which is of great interest in many industrial application. However, in addition to the usual difficulties of computer simulation of incompressible fluid motion and heat exchange, this flow also presents the added issue of involving severely truncated open boundaries. The most commonly used boundary conditions either cause numerical instabilities or have an exceedingly high computational cost. A two-dimensional simulation of the confined impinging jet at Re = 2500 with a non-dimensional nozzle-to-plate distance H/D = 2 has been used to test the effectiveness of alternative boundary conditions designed to correctly reproduce the physics of the phenomenon. A large eddy simulation of the three-dimensional case with the same parameters has been performed as well. In both cases, the boundary conditions prevented the divergence of the simulation and the production of non-physical reflections.