A numerical study based on large eddy simulation is performed to investigate a bottom boundary layer under an oscillating tidal current. The focus is on the boundary layer response to an external stratification. The thermal field shows a mixed layer that is separated from the external stratified fluid by a thermocline. The mixed layer grows slowly in time with an oscillatory modulation by the t...

Observations of turbulent kinetic energy (TKE) dynamics in the ocean surface boundary layer are presented here and compared with results from previous observational, numerical, and analytic studies. As in previous studies, the dissipation rate of TKE is found to be higher in the wavy ocean surface boundary layer than it would be in a flow past a rigid boundary with similar stress and buoyancy f...

Two different approaches have been used to calculate turbulent flow along a long thin cylinder where the flow is aligned with the cylinder. A boundary-layer code is used to predict the mean flow for very long cylinders (length to radius ratio of up to O(10)), with the effects of the turbulence estimated through a turbulence model. Detailed comparison with experimental results shows that the mea...

The turbulence regime in a quasi-stationary, horizontally evolving, and sheared boundary layer with bottom buoyancy forcing has been studied numerically by means of large eddy simulations (LES) in conjunction with its experimental investigation in a laboratory wind tunnel. The atmospheric prototype of the investigated boundary layer is commonly observed in the earth’s atmosphere during daytime ...

A series of supersonic wind tunnel tests on an ogive-cylinder body were performed to investigate the pressure distribution, the boundary layer profiles, and the flow visualization at various angles of attack. All tests were conducted in the trisonic wind tunnel of the Imam Hossein University. The theoretical shock angle at different model positions compared well with those we obtained via Schi...

[1] Boundary layer turbulence plays a central role in determining the strength of the overall atmospheric circulation by affecting the intensity of exchange of heat, mass, and momentum at the Earth’s surface. It is often parameterized using the bulk formula, in which the vonKarman parameter plays a critical role. Here we conducted a range of sensitivity simulations with an atmospheric general c...

The current study presents the results of the aerodynamic noise prediction of the flow field around a NACA 0012 airfoil at a chord-based Reynolds number of 100,000 and at 8.4 degree angle of attack. An incompressible Large Eddy Simulation (LES) turbulence model is applied to obtain the instantaneous turbulent flow field. The noise prediction is performed by the Ffowcs Williams and Hawkings (FW-...