Pressure Losses in Tube Bundles of Close Spacings

Summary

For a special plastic heat exchanger module the pressure drop outside the tubes at 17 staggered rows has been measured in a hot air test rig. The results can be expressed in form of a pressure loss coefficient dependent on the Reynolds-number. The closely packed tubes, caused by the manufacturing process, have transverse spacing ratios of 1.05. By a simple relation between loss coefficient, Reynolds-number and transverse spacing ratio the experimentell results can be extended to higher spacing ratios up to 1.50. The calculated results are in good correspondence with those of other authors obtained by experiments.