Peristaltic flow of nanofluid with temperature dependent viscosity in an annulus

Peristaltic flow in an annular region bounded by a concentric cylindrical tube is considered. The current study focuses on understanding enhancement of heat transfer in presence of nanoparticles. It also studies the effect of peristaltic motion on enhancement of heat transfer. The outer tube is subjected to a sinusoidal wave, and inner tube is rigid. Nanofluid has a variable viscosity which depends on temperature. Analytical solutions for temperature, velocity, and pressure gradient are evaluated and the effect of carbon nanotube is represented graphically. A method of regular perturbation is adopted to get an analytical solution. The impact of having single-walled carbon nanotubes (SNT) and multi-walled carbon nanotubes (MNT) on the parameters like pressure gradient, temperature, and velocity. Long wavelength approximation is assumed on a low Reynold’s flow. The impact of inner tube radius, amplitude of sinusoidal wave, and rate of flow on pressure gradient are analyzed for both SNT and MNT.