mixed convection is a fundamentally significant heat transfer mechanism that occurs in selection industrial and technological applications. in this study, first the laminar mixed convection inside rectangular enclosure with moving wall and aspect ratio=10 is modeled and then the results are compared with other investigate. after showing varity of results, the investigation is continued with tur...

To simulate the effect of free st ream turbulence on turbulent spot formation, experiments were conducted on the interaction of localized three-dimensional disturbances with the harmonic waves in a laminar boundary layer on a flat plate. Experiments conducted in three-dimensional diverging flow (but zero pressure gradient) show, while individually the disturbances decay downstream, their intera...

The effect of inlet conditions on the mixing of a passive scalar was investigated in a planar shear layer with inlet boundary layers that were laminar, tripped and naturally turbulent–transitional. Planar laser-induced fluorescence measurements of acetone were used to directly evaluate the shear layer structure, and were processed to determine probability density functions ~PDFs! of the mixture...

A wind-tunnel model was developed to study the two-dimensional turbulent boundary layer in adverse and favourable pressure gradients with out the effects of streamwise surface curvature. Experiments were performed at Mach 4 with an adiabatic wall, and mean flow measurements within the boundary layer were obtained. The data, when viewed in the velocity transformation suggested by Van Driest, sho...

We define turbulent-turbulent spot as a local concentration of vortices with high level of swirling strength originating from hairpin packet in a turbulent boundary layer. We also define bypass transition in the narrow sense as the breakdown of the Blasius boundary layer beneath freestream homogeneous isotropic turbulence with an initial amplitude of 1 to 4 percent. We present evidence for the ...

The interaction between circular synthetic jets and flat-plate laminar/turbulent boundary layers is investigated using CFD simulations in this study. For turbulent boundary layer simulations, large eddy simulation (LES) is applied so as to obtain more accurate flow details. The simulation results are validated using both existing experimental data and numerical results obtained from other resea...

A novel neuro-based method is introduced to solve the laminar boundary layer and the turbulent free jet equations. The proposed method is based on cellular neural networks, CNNs, which are recently applied widely to solve partial differential equations. The effectiveness of the method is illustrated through some examples.

A novel neuro-based method is introduced to solve the laminar boundary layer and the turbulent free jet equations. The proposed method is based on cellular neural networks, CNNs, which are recently applied widely to solve partial differential equations. The effectiveness of the method is illustrated through some examples.

The objective has been to study turbulent boundary layers under adverse pressure gradients (APG) through direct numerical simulation (DNS). The numerical code is based on a pseudo-spectral technique which is suitable for the simple geometry (flat plate) considered here. A large effort has been put into the optimization of the numerical code on various super computers. Five large simulations hav...