Efficient 2D Model of Flow Distribution in Dense Tube Bundles

Abstract

It is imperative that flow distribution is considered while designing heat exchanger tube bundles because it greatly influences equipment performance. What is more, a wide range of operating issues can occur if the distribution is significantly non-uniform. Since pressure gradients which, in fact, govern flow distribution can be adjusted via shape optimisation of individual parts of the flow system, such an action can not only improve performance but also increase reliability of the apparatus. Still, an efficient and accurate-enough flow model has to be available in order for the resulting optimisation model to be viable in terms of engineering practice. Heat exchangers often feature dense tube bundles which cannot be properly described via available simplified 1D models. Utilisation of computational fluid dynamics (CFD) or other computationally-intensive approaches, on the other hand, is not feasible either due to unacceptably long optimisation times. An efficient 2D flow distribution and pressure drop model is therefore presented. Additionally, a comparison of data obtained with the model for several tube bundle geometries and the corresponding data yielded by CFD is provided.