Impact of homogeneous–heterogeneous reactions on mixed convection flow of a copper–water nanofluid past a permeable shrinking cylinder with thermal radiation

The effect of thermal radiation on mixed convective flow of a copper–water nanofluid past a porous shrinking cylinder with homogeneous–heterogeneous reactions is studied. Using suitable transformations, the partial differential equations are converted into ordinary differential equations. The resulting self-similar equations are numerically solved using shooting method for several values of the pertinent parameters. Both assisting flow and opposing flow are considered in this study. The numerical results signify that the multiple solutions exist for the opposing flow, while for the assisting flow the solution is unique. The results also indicate that dual solutions only exist when a certain value of suction is implemented through the permeable cylinder. Further, the nanoparticle fraction and mixed convective parameter delay the boundary layer separation. A comparison is made with the available published data and is found to be in good agreement.