Computational analysis of entropy generation in three-dimensional mixed convection flow with thermal dissipation and variable thermal conductivity

Entropy generation in steady three-dimensional thermal flow is investigated under the coupled influence of viscous dissipation and mixed convection. The stretching sheet with an exponential velocity profile induces the flow. In this examination, we presume that the fluid is incompressible and possesses a Newtonian behavior and temperature-dependent thermal conductivity. Using the appropriate classical similarity variables reduces the dimensional nonlinear dynamical system of governing equations to a dimensionless nonlinear dynamical set of ordinary differential equations. It's important to note that the selection of an exponentially varying surface temperature is deliberate, as it enables precise similarity transformations to be established in situations involving both viscous dissipation and buoyancy forces. The simplified finite difference approach (SFDM) is used to solve the acquired nonlinear dynamical set of ordinary differential equations. The tridiagonal matrix approach is used to solve the resulting system of algebraic equations. In a particular situation, the present numerical simulation is numerically checked with the previously available results and observed a good agreement. The effects of physical parameters on velocity, temperature, surface stresses and heat tranfer rate, entropy generation, and the irreversibility parameter are investigated. The entropy generation rate exhibits a decreasing trend with respect to the mixed convection parameter in the vicinity of the stretching surface. Entropy reduction can be achieved by employing a working fluid with a low Prandtl number and by minimizing the fluid friction.

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This study investigates the entropy generation in steady three-dimensional thermal flow under the combined influence of viscous dissipation and mixed convection. The governing equations are reduced to a dimensionless nonlinear set of ordinary differential equations using classical similarity variables. The simplified finite difference method is employed to solve the resulting equations, and good agreement is observed with previous results. The effects of physical parameters on various flow and heat transfer variables, as well as entropy generation rate, are examined. A decreasing trend in entropy generation rate is found near the stretching surface with respect to the mixed convection parameter, and entropy reduction can be achieved by using a fluid with low Prandtl number and minimizing fluid friction.