Mixed convective flow of CNTs nanofluid subject to varying viscosity and reactions

Abstract

Abstract The addressed work explains SWCNTs (Single walled carbon nanotubnes) and MWCNTs (Multi walled carbon nanotubnes) nanofluid flow under the influences of temperature dependent viscosity and mixed convection. Comparative study of SWCNTs and MWCNTs suspended in base liquid is presented. Further heat and mass transfer are addressed for nanofluid effected by radiation, heat generation/absorption and diffusion species. Mathematical development of problem is taken in cylindrical coordinates. System of highly nonlinear differential equations are constructed via appropriate transformations. The system of equations are tackled numerically by bvp4c MATLAB solver. The findings of the study show that larger volume fraction $$\left( \phi \right)$$ ϕ contributes to enhance the nanoliquid flow. The velocity by submerging MWCNTs is noted higher than SWCNTs. Furthermore, the relationship between the viscosity variable $$\left( \theta _{r}\right)$$ θ r and the temperature is such that the temperature near the surface decreases with increase in $$\left( \theta _{r}\right)$$ θ r , while at the same time the temperature away from the surface increases. Subsequently, higher temperature is observed in SWCNTs-liquid compared to the MWCNTs-liquid to the similar values of $$\left( \theta _{r}\right)$$ θ r . Further, heat transfer is an increasing function of varying viscosity variable $$\left( \theta _{r}\right)$$ θ r .