Numerical study of flow and heat transfer in novel structure packed beds

A forced convection heat transfer inside micro pores of structure packed beds with spherical or ellipsoidal particles are numerically studied in this paper. Three-dimensional Navier-Stokes equations and RNG k-ε turbulence model with scalable wall function are adopted for present computations. The effects of packing form and particle shape are carefully studied and the flow and heat transfer performances in uniform and non-uniform packed beds are also compared in detail. The macroscopic hydrodynamic and heat transfer results are obtained from micro pore cells by using integrating method. The results show that, with the same physical parameters, the pressure drops in structure packed beds are much lower than those in randomly packed beds while the overall heat transfer efficiencies (except SC packing) are much higher. The traditional correlations of flow and heat transfer extracted from randomly packings are unavailable for structured packings, and some modified correlations are obtained. Furthermore, it finds that, with the same particle shape (sphere), the overall heat transfer performance of SC packing is better than that of BCC packing. With the same packing form (BCC), the overall heat transfer performance of spherical particle model is better than that of ellipsoidal particle model and with the same particle shape and packing form (BCC packing with sphere), the overall heat transfer performance of uniform packing is better than that of non-uniform packing.