A model was developed for the analysis of steady and unsteady bubble generation frequencies in a microfluidic flow-focusing device. In both cases, the generation frequency depends on the downstream influence of bubbles created by the flow-focusing device, which provides a source of feedback. For steady-state generation of bubbles, this feedback explains the relationships among frequency, gas pr...

the present work is focused on the performance analysis of a 1.7 liter engine with turbocharger. the ultimate target is studying the response of the turbocharger to the inlet pulsating flow. such numerical analysis requires the time variation of pressure and velocity at turbine inlet. in order to achieve such information, one dimensional unsteady viscous compressible flow within a 1.7 liter tur...

Molecular dynamics (MD) simulation is used to study slip at the fluid-solid boundary in an unsteady flow based on the Stokes’ second problem. An increase in slip is observed in comparison to the steady flow for shear rates below the critical shear rate of the corresponding steady flow. This increased slip is attributed to fluid inertial forces not represented in a steady flow. An unsteady mathe...

AD-P004 168 AD-P004 169 TITLE: Superroaneuverability. Wing Rock Flov Phenomena. Potential Applications of Forced Unsteady Flows. Unsteady Stall Penetration of an Oscillating Swept Wing. Simultaneous Flow Visualization and Unsteady Lift Measurement on an Oscillating Lifting Surface. A Visual Study of a Delta Wing in Steady and Unsteady Motion. Comparative Visualization of Accelerating Flow aroun...

We present our recent results on the Prandtl-Meyer reflection for supersonic potential flow past a solid ramp. When a steady supersonic flow passes a solid ramp, there are two possible configurations: the weak shock solution and the strong shock solution. Elling-Liu’s theorem (2008) indicates that the steady supersonic weak shock solution can be regarded as a long-time asymptotics of an unstead...

Global-stability theory is used to predict the onset of flow unsteadiness based on steady solutions of the Reynolds Averaged Navier–Stokes equations. The stability problem is formulated for compressible flow at moderately-high Reynolds numbers, using a turbulence model to provide closure for the averaged Reynolds stresses. The approach provides an efficient method for predicting the occurrence ...

The present paper describes how to apply the Chebyshev orthogonal collocation technique to solve steady-state and unsteady-steady two-dimensional problems. All problems are solved using one single computer algebra, Mathematica . The problems include: (1) steady-state heat transfer in a rectangular bar, (2) steady-state flow in a rectangular duct, (2) steady-state heat transfer in a cooling cyli...

The work presents an artificial compressibility method applied to incompressible Navier-Stokes equations for steady as well as for unsteady flows. Two modifications of unsteady numerical solution by an implicit finite volume method are considered. First one uses large artificial compressibility parameter and the iterative solution approximates unsteady evolution of flow. The second approach int...

hydraulic simulation of water flow in irrigation canals may reveal management shortcomings and help managers find solutions to them. hydraulic simulation models can be appropriate tools for understanding hydraulic behavior of irrigation systems. in the present study, the steady state hec-ras model was tested and compared with the mike 11 unsteady state model. a secondary irrigation canal in the...