Peter Gospodinov, Vladimir Roussinov, Mirona Mironova. Cylindrical nonisothermal oscillatory Couette gas flow in the slip regime: Wall shear stress and energy transfer, numerical investigation
Natural Sciences / Physics / Fluid Dynamics
Submitted on: Feb 19, 2014, 10:46:52
Description: The oscillatory Couette flow between an oscillating inner cylinder and a stationary outer cylinder is considered in the study. New results for the stress and heat flux at the "gas-cylinder wall" interface are obtained. The continuum model based on the Navier-Stokes equations for compressible fluid is completed with the equations of continuity and energy transport. Along with the numerical solution proposed in our previous paper [29], it is used to investigate the cylinder-gas interaction. The wall shear stress (drag) and heat flux variation at the cylinder walls are numerically investigated. First order velocity-slip boundary conditions are specified referring to two types of motion of the inner cylinder- harmonic oscillations and stepwise oscillations. Two types of energy transfer boundary condition at inner cylinder are considered - inner cylinder with constant wall temperature and adiabatically insulated inner cylinder. Results found for the drag and heat flux variations are presented accounting for different oscillation frequencies and Knudsen numbers. Parts of the results obtained for the harmonically oscillating inner cylinder are compared to the numerical data, obtained by the DSMC method in [18]. In the case of harmonically oscillating inner cylinder a drag phase delay with respect to the wall velocity is established and studied. Hydrodynamic selfsimilarty of the drag and energy transfer variations is confirmed and analyzed.