Lubricating hot stretching membrane with a thin hybrid nanofluid squeezed film under oscillatory compression

Abstract

The small-amplitude oscillatory compression is used in many micromachines to measure various properties of molten polymers and has several advantages over rotational devices due to a less sophisticated mechanism and the lower cost. In this article, an oscillatory squeezing flow of GO–MoS2 hybrid nanofluid mixed in C2H6O2–H2O is considered over a variably hot stretching elastic membrane. The two-dimensional unsteady heat convection problem is modeled by the Navier–Stokes and the energy conservation equations. The normalized governing equations are solved with an advanced fourth-order numerical finite-difference scheme. Various characteristics of the flow and the heat transfer phenomena, such as the velocity and the temperature profiles, the skin-friction drag and the heat transfer rate at lower wall, are calculated and analyzed through several graphs and tables. The results reveal that the forward and backward flow strongly depends upon the amplitude of compression. A 30% increase in the amplitude of compression oscillation results in 109% increase of heat transfer rate from fluid to stretching membrane without altering the frictional drag significantly. Further, adding 8% concentration of GO–MoS2 hybrid nanofluid enhances the heat transfer rate from fluid to membrane by 21.4%. Moreover, as the Strouhal number increases from 1 to 6 the heat transfer rate from fluid to membrane increases up to 77.6%.