The multipass exchanger is limited in its performance because some tubes have countercurrent flow and others have parallel flow. Increasing thermal effectiveness and improving the correction factor would be desirable. By having an odd number of tube passes, improvement can be achieved. When the shell fluid is unmixed, better results can be obtained. The effect of unmixed shell fluid is examined in the present study.

KEYWORDS: efficiency, heat exchangers, performance, heat flow, fluid flow, counterflow heat exchangers