Unsteady squeezing flow of magnetohydrodynamic carbon nanotube nanofluid in rotating channels with entropy generation and viscous dissipation

The most favorable gift of modern science is nanofluid. The nanofluid can able to move freely through micro channels with the spreading of nanoparticles. Due to improved convection between the base liquid surfaces and nanoparticles, the nano suspensions express high thermal conductivity. Also, the benefits of suspending nanoparticles in base fluids are increased heat capacity, surface area, effective thermal conductivity, collision, and interaction among particles. This research aim to study squeezing flow of carbon nanotubes based on water (H2O) in rotating channels. Entropy generation is evaluated and for this purpose, second law of thermodynamics is employed. The influences of thermal radiation, viscous dissipation, and applied magnetic field on nanofluid are taken into account. The flow of the nanofluid is considered in unsteady three dimensions. The transformed ordinary differential equations (ODEs) are solved by homotopy analysis method with the help of similarity variables. Results obtained for single and multi-wall carbon nanotubes are compared. Plots have been presented in order to examine how the velocities, temperature, and entropy profiles become affected by numerous physical parameters. Generally, the velocity profiles escalate when the upper plate of the channel moves toward the lower stretching one and reduces when the upper plate is moving away from the lower one. The velocity profile in y-direction escalates with the escalation in nanoparticle volume fraction and suction parameter while the rotation parameter bids dual behavior with the escalating values. The velocity profile in x-direction bids the oscillatory behavior with the enhancement in nanoparticle volume fraction, rotation parameter, and magnetic parameter. The physical properties of carbon nanotubes, thermo physical properties of carbon nanotubes and nanofluid of some base fluids, and thermal conductivity of carbon nanotubes with different volume fractions are shown through tables.