Experimental Investigation of Heat Transfer Enhancement in a Double Pipe Heat Exchanger Using Compound Technique of Transverse Vibration and Inclination Angle
Abstract
Numerous tests are recently conducted to assess vibration's role in accelerating the heattransfer rate in various heat exchangers. In this work, the enhancement of heat transfer bythe effect of transfer vibration and inclination angles on the surface of a double pipe heatexchanger experimentally has been investigated. A data acquisition system is applied torecord the data of temperatures, flow rates, and frequencies over the tests. A compoundtechnique was adopted, including the application of a set of inclination angles of (0°, 10°, 20°,and 30°) under the effect of frequency of vibration ranging from sub-resonance to overresonancefrequencies. The results showed that the overall heat transfer coefficientenhances by applying the compound technique at all the working fluid's temperatures andflow rate ranges. The maximum increase in overall heat transfer coefficient occurs at anangle of 30° and the resonance frequency. Moreover, the effectiveness of the double pipeheat exchanger gradually expanded when temperature, inclination angles, and vibrationamplitude rosed. But the effectiveness value declined as the hot working flow rate increasedconsiderably. Finally, the enhancement factor demonstrated that the combined strategy(vibration frequencies and inclination angles) had been the most effective technique inimproving and enhancing heat transfer and was superior to the other ways. Additionally, theextremes improvement in overall heat transfer coefficient, effectiveness, and enhancementfactor are 183.4, 191, and 164.4 %. The improvement was situated at the resonancefrequency with a 30° inclination angle.Keywords: Double pipe heat exchanger, Inclination
Keywords
Double pipe heat exchanger, Inclination angle, Resonance frequency, Enhancement factor, EffectivenessMetrics