Experimental investigation on heat transfer in double pipe heat exchanger employing triangular fins

Abstract

Various experiments were carried out for this dissertation to investigate and compare the heat transfer in a DPHE for counter flow arrangement studying with and without usage of longitudinal triangular fins. The test section is a horizontal annular passage formed by copper tube with an inner diameter 15 mm to outer diameter 19 mm with a length of 1000 mm. Triangular fin with dimensions of 9 mm base, 8 mm height and 2 mm thickness are used in the present study. In the beginning we conducted the experiment with the traditional DPHE to analyze the effectiveness parameter for plane heat exchanger and then with 4 longitudinal triangular fins with difference in spacing of fins angle 90 degrees of length 1000 mm. The effects of the fins spacing and mass flow rate of fluid is examined on the thermal performance of heat exchanger. Increase in flow rate of cold fluid results in increase of heat transfer and effectiveness increases to 0.505 in longitudinal triangular finned tube from the value 0.405 in the traditional DPHE of counter flow respectively. Another performance parameter like overall heat transfer coefficient increases and LMTD throughout the experiment decreases respectively.