Dynamic stall has been a technical challenge and fluid dynamical subject of interest for more than fifty years; but in the last decade significant advances have made understanding, prediction, modeling, control dynamic on rotors. This paper provides summary state art experiments future directions understanding Experimental data sets are discussed, as well direction research stall. Coordinated t...

Numerous experiments have been conducted on plunging Eppler 361 airfoil in a subsonic wind tunnel. The experimental tests involved measuring the surface pressure distribution over the airfoil at Re=1.5×105. The airfoil was equipped with Gurney flap(heights of 2.6, 3.3 and 5% chord) and plunged at 6cm amplitude. The unsteady aerodynamic loads were calculated from the surface pressure measurement...

The flow hydrodynamics in a low specific speed radial pump-turbine reduced scale model is experimentally investigated under off-design operating conditions in generating mode. Wall pressure measurements, in the stator, synchronized with high-speed flow visualizations in the vaneless space between the impeller and the guide vanes using air bubbles injection are performed. When starting from the ...

An unsteady nonlinear and extended version of the Moore-Greitzer model is developed to facilitate the synthesis of a quasilinear stall vibration controller. The controller is synthesised in two steps. The first step defines the equilibrium point and ensures that the desired equilibrium point is stable. In the second step, the margin of stability at the equilibrium point is tuned or increased by...

In the recent years, the main obstacles for raising the operating efficiency are instabilities of the compressor system. The related dynamics and control schemes then cause lots of interests among engineers and researchers. Two main phenomena, which cause the instabilities, are the “surge” and the “stall” behaviors of the compressed gas. The so-called “surge” is characterized as a one-dimension...

In order to explore the internal relationship between stall core propagation and flange leakage flow in rotating of a mixed-flow pump, based on k-? turbulence model, SIMPLEC algorithm hexahedral structured grid are used simulate field pump. By setting clearance as 0.2 mm, 0.5 mm 0.8 characteristics unsteady pump under condition near studied, influence pressure fluctuation is analyzed. The resul...

In order to understand the effects of the unsteady aerodynamic excitations in complex flow field on blades, on the basis of the data obtained from the single-stage axial flow compressor, three kinds of exciting forms in the compressor had been studied, including the correlation between excitations and responses in the upstream blade row wake, inlet distortion and rotating stall. Results showed ...