A comprehensive entropic scrutiny of dissipative flows over a thin needle featured by variable thermophysical properties

Abstract

The transfer of heat and entropy in an incompressible fluid over a thin needle surface is numerically examined. The results of frictional heating are explored by including the dissipation function in the energy equation. The thermophysical characteristics of the viscous fluid are assumed dependent on the temperature. The reduction of the governing equations to a system of ordinary differential equations is done via adequate similarity variables, in which the differential quadrature method (DQM) is utilized to compute the numerical solutions. The resulting equations are also solved using a routine known as bvp4c to make sure the accuracy of the implemented numerical method. The variations of the quantities of interest with the emerging key parameters, such as the thin needle size, the velocity ratio, the variable viscosity parameter, the Prandtl number, the thermal conductivity parameter, and the Eckert number are graphically illustrated and discussed. It has been noticed that as the needle size decreases, so does the temperature and the entropy generation.