(565c) Research On the Enhanced Heat Transfer in Shell and Tube Heat Exchanger Based On Flow Path Optimization Idea

In this paper, a novel heat transfer enhancement idea called flow path optimization idea was presented. By analytical calculation and numerical calculation, the new idea quantified the effect of flow pattern, flow path dimension, flow path division and geometric construction of element on the hydraulic performance and thermodynamics performance of the shell and tube heat exchanger. The new idea could provide heat exchanger with enhanced heat transfer elements with optimized flow path for specific case, and it also could offer simple rapid algorithm to predict the heat transfer rate and pressure drop of heat exchanger combined with multiple enhanced heat transfer elements, the elements contained the insert elements, rough surface and extended surface tubes, enhanced supporting elements (baffles), etc. Two industrial unit renovation examples, including one helical baffles heat exchanger with varied helical angles and one heat exchanger with finned tube and rod baffles were studied using the flow path optimization idea. The increased heat transfer rate were 32% and 13% respectively, the decreased pressure drop were 23% and 58% respectively, and the calculation errors were within 10%.