Heat Transfer and Flow Structures of Laminar Confined Slot Impingement Jet with Power-Law Non-Newtonian Fluid

Abstract

Heat transfer performances and flow structures of laminar impinging slot jets with power-law non-Newtonian fluids and corresponding typical industrial fluids (Carboxyl Methyl Cellulose (CMC) solutions and Xanthangum (XG) solutions) have been studied in this work. Investigations are performed for Reynolds number Re less than 200, power-law index n ranging from 0.5 to 1.5 and consistency index K varying from 0.001 to 0.5 to explore heat transfer and flow structure of shear-thinning fluid and shear-thickening fluid. Results indicate that with the increase of n, K for a given Re, wall Nusselt number increases mainly attributing to the increase of inlet velocity U. For a given inlet velocity, wall Nusselt number decreases with the increase of n and K, which mainly attributes to the increase of apparent viscosity and the reduction of momentum diffusion. For the same Re, U and Pr, wall Nusselt number decreases with the increase of n. Among the study of industrial power-law shear-thinning fluid, CMC solution with 100 ppm shows the best heat transfer performance at a given velocity. Moreover, new correlation of Nusselt number about industrial fluid is proposed. In general, for the heat transfer of laminar confined impinging jet, it is best to use the working fluid with low viscosity.

Utilization of wavy porous layer, magnetic field and hybrid nanofluid with slot jet impingement on the cooling performance of conductive panel

“…It was noted that many studies were needed to shed some light on the processes because of the uncertainties in the interactions of different parameters and presence of complicated random processes. J-I cooling has been considered with nanofluids by taking into account the nanoparticles shape effects (Shirvani et al , 2021, Selimefendigil and Öztop 2017a), curvature of the cooled surface (Chen and Cheng 2020, Selimefendigil and Öztop 2017b) and non-Newtonian aspects of the nanofluid (Lamraoui et al 2019, Qiang et al , 2018, Yousefi-Lafouraki et al , 2016, Selimefendigil, Oztop and Chamkha 2021b).…”

A Numerical and Experimental Investigation of Dimple Effects on Heat Transfer Enhancement with Impinging Jets

“…Nuntadusit et al [8] investigated the effect of using multiple swirling impinging jets (MSIJs) and found that the Nu from using MSIJs was higher than from using multiple conventional impinging jets. Qiang et al [9] studied the low viscosity fluid (non-Newtonian fluid) impinging to the flat plate. The results indicate that non-Newtonian fluid is the optimum choice to obtain high heat transfer rate for laminar flow.…”