Large Eddy simulation and Reynolds-averaged Navier-Stokes modeling of flow in staggered plate arrays: Comparison at various flow regimes

In this paper three flow-modeling strategies are employed to study the evolution of the three-dimensional turbulent flow characteristics and heat transfer mechanisms with the Reynolds number in staggered plate arrays: steady RANS, steady laminar and the LES approach. In the RANS modeling framework k-ε realizable, k-ω SST and RSM turbulence models are used. This paper also compares the accuracy of RANS and laminar steady models with LES simulation for 300 ≤ Re ≤ 9000 which corresponds to the Reynolds number range encountered in offset strip fins (OSF) heat exchangers. Analysis of numerical results from global and local points of view shows great dispersion especially in the transitional flow regime. Moreover the RANS turbulent model that produces the best predictions cannot be known a priori.