FLUID-FLOW AND HEAT-TRANSFER FOR TUBE ROW S AND BUNDLES AT LOW VALUESOF THE REYNOLDS-NUMBER .1. ONE ROW OF TUBES WITH IN-LINE ARRANGEMENT OF THE TUBES

Cross flow around tube bundles is one of the most important basic proc esses of heal transfer. At higher values of the Reynolds number Re exp erimental methods are applied. Nowadays numerical methods are equivale nt. Their range of application is, however, limited to lower values of Re, where experimental methods fail. They can give us an insight into physical details of fluid flow and heat transfer for tube rows and tu be bundles. In the first part of the report, fluid flow around alignme nts of two and three tubes is investigated with a finite element techn ique. The Reynolds number and the distance between the tubes are varie d. Special attention is paid to vortex formation between the tubes. In addition the results for heat exchange between the tubes and the surr ounding fluid are discussed. All results are compared with those from other authors.