Application of CFD to closed-wet cooling towers

Computational fluid dynamics (CFD) is applied to predicting the performance of closed-wet cooling towers (CWCTs) for chilled ceilings according to the cooling capacity and pressure loss. The prediction involves the two-phase flow of gas and water droplets. The predicted thermal performance is compar ed with experimental measurement for a large industrial CWCT and a small pr ototype cooling tower. CFD is then applied to the design of a new cooling t ower for field testing. The accuracy of CFD modelling of the pressure loss for fluid flow over the heat exchanger is assessed for a range of flow velo cities applied in CWCTs. The predicted pressure loss for single-phase flow of air over the heat exchanger is in good agreement with the empirical equa tion for tube bundles. CFD can be used to assess the effect of flow interfe rence on the fluid distribution and pressure loss of single- and multi-phas e flow over the heat exchanger. (C) 2000 Elsevier Science Ltd. All rights r eserved.