Author : Juber T. Patel and Manish H. Attal

The heat transfer characteristics of pulsating turbulent air flow in pipe under different conditions of Reynolds number, pulsation frequency, pulsator location are investigated experimentally. A tube wall of uniform heat flux condition is considered for this case. Reynolds number varies from 7000 to 16500 while the frequency of pulsation is ranging from 1Hz to 3.33Hz. With installing the pulsation mechanism downstream of tested tube exit, results shows that Nusselt number is strongly affected by both pulsation frequency and Reynolds number. The maximum enhancement obtained in heat transfer coefficient is 44.4% at downstream and 17.7% at upstream at pulsation frequency of 3.33Hz. It is also observed that relative mean Nusselt number increases depending upon frequency range. The main implication of these results is that flow pulsation can be used in industrial heat exchangers to improve heat transfer coefficient and reduce operating cost.

Keywords: Pulsating flow, Heat transfer enhancement, Turbulent flow, Pulsator.

Article published in International Journal of Current Engineering and Technology, Vol.6, No.5 (Oct-2016)