NUMERICAL STUDY ON HEAT-TRANSFER AND PRESSURE-DROP IN MULTILOUVERED FINS

To determine the optimum combinations among geometrical parameters of multilouvered fins, a numerical study was performed with a two-dimensi onal finite difference code. The code was developed by the authors usi ng an overlaid grids method. The numerical results showed that the exi stence of the optimum ratio of fin-pitch/louver-pitch for each louver angle. The effects of thermal wakes on the heat transfer characteristi cs were discussed from the numerical results to understand the correla tion between the fin geometries and heat transfer characteristics. Thi s discussion concluded that the control of the thermal wakes after lou vers was a key point for the optimization of multilouvered fins. A sim ple numerical expression was proposed to estimate the optimum relation among the fin parameters. The numerical expression was evaluated thro ugh the discussion about the effects of the fin parameters and perform ance of heat exchangers composed of multilouvered fins. Also, it was o btained that a heat exchanger with smaller louver angle (theta) had su perior performance in the range of 20 degrees less than or equal to th eta less than or equal to 30 degrees.