Direct numerical simulations are extended to see the effects of time-periodic blowing frequency from a spanwise slot on a turbulent boundary layer. The time-periodic blowing frequency is given in a range 0≤f≤0.08 at a fixed blowing amplitude of A=0.5. The effects of the blowing frequency are scrutinized by examining the phaseor time-averaged turbulent statistics. A most effective blowing freque...

Direct numerical simulations of the Navier–Stokes equations have been carried out with t § he objective of studying turbulent boundary layers in adverse pressure gradients. The boundary layer flows concerned are of the equilibrium type which makes the analysis simpler and the results can¨be compared with earlier experiments and simulations. This type of turbulent boundary layers a © lso permits...

A novel immersed boundary (IB) method has been developed for simulating multi-material heat transfer problem – a cylinder in a channel heated from below with mixed convection. The method is based on a second-order velocity/scalar reconstruction near the IB. A novel algorithm has been developed for the IB method to handle conjugate heat transfer. The fluid–solid interface is constructed as a col...

A problem of great concern in aviation and submarine propulsion is the control of the boundary layer and, in particular, the methods to extend the laminar region as a means to decrease noise and fuel consumption. In this paper we study the flow of air along an airfoil when a layer of ionized gas and a longitudinal electric field are created in the boundary layer region. By deriving scaling solu...

in this study, the dispersion mechanisms of aerosols suspended in a turbulent plane channel flow is investigated using a novel numerical approach. a turbulent channel flow is simulated by a direct numerical simulation (dns) method, for which no-slip boundary conditions are assumed at the top and bottom walls, while periodicity conditions are applied on the other sides. dns, in particular, allow...