EXPERIMENTAL INVESTIGATION OF PRESSURE DROP CHARACTERISTICS ACROSS RECTANGULAR CHANNEL USING DETACHED RIBS

Abdul Rahman, Anandkumar S Malipatil

Abstract: In the present day it is very necessary to find heat transfer characteristics of heat exchanger, heat exchanger as an important appliances widely used in day to day life, like in industry, home appliances, gas turbine, transportation, power production, in aircraft etc. the improvement of heat transfer performance of heat exchanger can be done by using insertion of vortex generators across rectangular channel. The experimental study is conducted to examine the pressure drop characteristics across rectangular duct with different geometrical configuration of detached ribs, Detached Ribs as vortex generators are inserted 90° in a rectangular duct having different aspect ratio (AR) of 1.4,1.8, 3,3.6. The effect of width, pitch ratio (P/H) of inserting vortex generator, flow direction and aspect ratio of duct are examined for Reynolds numbers (Re) based on hydraulic diameter of rectangular duct Dh, and it is in the range of 8000 to 24000. The results shows if pitch to height increases friction factor ratio decreases by 28.98% , if Reynolds number increases , 8.34% time friction factor ratio increases , if aspect ratio increases friction factor ratio decrease by 80.03%. The experiment is repeated for different AR of vortex generators 1.4,1.8, 3,3.6. pitch ratio (P/h), width 16.07mm, 12.5mm, 7.5mm,6.25mm, for different Re = 8000, 12000, 16000, 20000, 24000.

Keywords: Rectangular Duct, Detached Ribs, Pressure Drop, Vortex Generator, Aspect Ratio, Friction Factor Ratio

DOI: https://doi.org/10.15623/ijret.2016.0509006