Hydraulic and thermal performances of a novel configuration of high temperature ceramic plate-fin heat exchanger

A novel fin configuration for high temperature ceramic plate-fin heat exchanger (PFHE) was developed using the three-dimensional computational fluid dynamics (CFD) FLUENT code. Numerical analysis was carried out for different types of fins and their results were compared with the selected design. The working fluids used in the model were sulfur trioxide, sulfur dioxide, oxygen and water vapor. Fluid flow, heat transfer, pressure drop and properties like Nusselt number, friction factor and j-factor were studied for various fin configurations. The rip saw fin design (case 9) with thickness of 0.05 mm gives the maximum heat transfer performance with less pressure drop and friction factor. The numerical result was compared with the analytical result for rectangular fins and they were found to be in reasonable agreement. In addition to it, the results from the selected ripsaw design were compared with the result from the model with no fins (case 1). It was found that thermal enhancement factor of 2.3211 and average Nusselt number of 4.215 was obtained for the selected design. The results of the rip saw fin design were found in good agreement with the analytical results of a rectangular fin. Further effects of Reynolds number on pressure drop and Nusselt number were studied.