International Journal of Thermal Sciences, vol.171, 2022 (SCI-Expanded)
© 2021 Elsevier Masson SASThe effects of using convergent, convergent-divergent and divergent conical wire coils in ethylene glycol and water mixture flow region on the augmentation of heat transfer are experimentally analyzed. Three different volumetric ratios (0:100), (20:80) and (40:60) of ethylene glycol and water, convergent, convergent-divergent and divergent conical wire coils with two different pitch ratios 2 and 3 are intended for the experiments. The experiments are conducted under the turbulent flow conditions Reynolds number ranging from 4627 to 25,099 and constant heat flux. The use of conical wire coils enhance both the heat transfer rate and fluid friction, whereas adding the ethylene glycol on pure water decreases the heat transfer rate and friction factor is slightly increased. The highest Nusselt number is obtained as 558 for the divergent conical wire coil with pitch ratio of two at Reynolds number of 22,846 in the case of using a fluid type with a (40:60) volumetric ratio. The highest performance evaluation criteria of 1.62 is achieved for the divergent wire coil insert P/D = 2 is used at lowest Reynolds number for Ethylene glycol:Water-0:100 fluid type. New correlations are modelled to predict the Nusselt number and friction factor. Therefore, making the currently investigated configurations a potential technique to increase the thermohydraulic performance of the engineering applications.