The second law analysis in free convective flow of pseudoplastic and dilatant fluids over a truncated cone with viscous dissipation: Forchheimer model

This work explores the second law analysis in the pseudoplastic, Newtonian and dilatant fluid flows over a truncated cone situated in a Forchheimer type of non-Darcy porous medium. The influence of viscous dissipation and thermal dispersion parameters on this free convective flow is studied in the presence of nonlinear Boussinesq approximation. The primary focus of this work is to have a clear idea about entropy generation in the flow of pseudoplastic, Newtonian and dilatant fluids over a truncated cone. Due to a complex nature of flow governing equations, the combination of local non-similarity approach and spectral local linearization method is found to be more accurate in comparison with other spectral methods; hence, this combination is proposed to discuss the solution of system of equations. An error analysis is employed to check the relevance of utilizing the spectral method for this kind of flow governing equations. In addition to this, the comparisons with the existing results, in particular cases are also inserted to show correctness and validity of the results. The study of physical quantities reveals that Nusselt number, entropy generation rate and Bejan number are higher for the dilatant fluid in comparison with the pseudoplastic and Newtonian fluids with or without above-mentioned effects. Increments in heat transfer and entropy generation rates are noticed with streamwise coordinate (xi) for all the fluids in the presence and absence of these effects which imply that heat transfer and entropy generation rates for the flow over a truncated cone lie between the flow over a full cone and a vertical plate.