The Effect Of Hydraulic Diameter Variations and Distance of Rods Square Profile in Rectanguler Channel

This study investigation about the convection heat transfer coefficient in a fluid flow entering the channel that is influenced by the fluid flow pattern. Turbulence influences the amount of heat transfer rate that occurs from the fluid to one of the cooled channel walls. To cause a turbulence effect, it is done by placing a row of squad rod profile disturbing rods in the middle of the cross-sectional width of the rectangular channel (300 mm x52 mm x234 mm). There are three variations of hydraulic diameter (db) that are used, namely 13 mm, 26 mm, and 39 mm. while the variations in the distance between the disturbing rods were 52 mm and 104 mm. This experiment was carried out in a test section in the rectangular channel with a temperature of ± 500C in a vertical direction from top to bottom with a variation of the Reynolds number from 50 to 500. This study resulted in different Nusselt numbers with variations in db and variations in Pb on the Reynolds number function. From the results of the experiment and analysis, it was found that the variation of db = 39 mm with Pb = 52 mm resulted in the largest Nusselt number compared to other variations.