Numerical investigation of louver edges effect on the performances of louvered fin compact heat exchanger.

Abstract

The rectangular channel louvered-fin compact heat exchanger (LFCHE) is the most efficient type that has been served in a radiator. However, with this type of heat exchanger, the pressure drop rises by three to four times as the heat transfer increases, which results in decreasing performance. This research is aimed to numerically investigate the louver edges (vertical, inclined, and horizontal) effect on LFCHE performance at different louver angle (θ) with air inlet velocities ranging from 1 to 30 m/s. A total of twelve models are made and simulated. The result revealed that the horizontal edge decreases the pressure drop up to 24.2% with a 1.01% increase in outlet air temperature over the base model (inclined edge). Thus, louver edge has design which results in higher and lower effect on pressure drop and temperature change, respectively. The research investigated the effects of louver edges using different performance evaluation criteria. At 10 m/s (Relp = 972.33) the horizontal edge increases the volume goodness (<i>jf</i>) factor up to 21.49% over the base model. Similarly, the horizontal edged fins resulted in maximum increment of <i>jf</i>-factor by 22% and 25% as compared with inclined edge for louver angles θ of 24 ° (at low Relp) and 20 ° (at high Relp), respectively. Generally, the horizontally edged LFCHE is proven to have higher performance in cooling the coolant with a minimum air side pressure drop.