...Angelo Pasini; Lucio Torre; Angelo Cervone; Luca d’Agostino The paper illustrates the results of an experimental campaign conducted in the Cavitating Pump Rotordynamic Test Facility at ALTA S.p.A., aimed at characterizing the rotordynamic forces acting on a whirling four-bladed, tapered-hub...

... approximately equals the exit diameter of the supersonic nozzle. 05 01 2011 22 08 2011 24 10 2011 24 10 2011 blades compressible flow confined flow flow instability flow visualisation impellers nozzles rotors shear turbulence stratified flow supersonic flow Pressure...

... (AOK TFR). The results show that pressure fluctuations at the impeller rotating frequency and some lower frequencies dominated in the semispiral suction chamber. Pressure fluctuations at the blade passing frequency, the impeller rotating frequency, and their harmonic frequencies were identified...

...Yuka Iga; Kei Hashizume; Yoshiki Yoshida In the present study, numerical analysis of a cavitating three-blade cyclic flat-plate cascade was performed considering cavitation surge, which is a type of cavitation instability in pumping machinery. A numerical method employing a uniquely developed gas...

...Douglas Bohl; Akshey Mehta; Naratip Santitissadeekorn; Erik Bollt The flow field in a cylindrical container driven by a flat bladed impeller was investigated using particle image velocimetry (PIV). Three Reynolds numbers (0.02, 8, 108) were investigated for different impeller locations within...

... fields lying within the evaluated uncertainties. Numerical data allowed the analysis of further details of the flow that could not be measured, like load conditions of the single blades, interaction of the propeller wake with the rudder, and pressure oscillations induced by the propeller on the vault...

...Yoshiki Yoshida; Hideaki Nanri; Kengo Kikuta; Yusuke Kazami; Yuka Iga; Toshiaki Ikohagi The relationship between the thermodynamic effect and subsynchronous rotating cavitation was investigated with a focus on cavity fluctuations. Experiments on a three-bladed inducer were conducted with liquid...

... with such a characteristic curve is that at runaway, the machine may switch back and forth from generating to reverse pumping modes. Moreover, it is well known that such unstable operation leads to a significant increase of structural vibrations and noise. blades bubbles channel flow flow separation flow...

... Sealing Technology: Principles and Applications , CRC Press , Boca Raton, FL , pp. 107 – 109 . 20 08 2010 06 04 2011 12 05 2011 12 05 2011 blades crude oil machine bearings mathematical analysis prototypes pumps seals (stoppers) shafts sliding friction...

... blade row) was selected with rotor and stator blade number kept constant. A generic undersea vehicle hull shape was chosen and the maximum shroud radius was required to lie within this body radius. A cylindrical rim-driven electric motor capable of generating a specific horsepower to achieve the design...

... characteristic. 20 09 2010 17 03 2011 11 05 2011 11 05 2011 blades channel flow flow instability flow simulation hydraulic turbines pumps rotors stators vortices rotating stall stationary vortex formation unsteady vortex formation S-shape, unstable characteristic...

... method and a hydraulic loss model with a variable correction factor. The blade thickness blockage effect on the flow was taken into account. The method was validated with the experimental data of the existing 17 inducers found in references. Moreover, the curves showing the relation of the correction...

...David Greenblatt On the basis of a semi-empirical model, large Gurney flaps of 10%, 20%, and 30% of the fan blade chord length were tested in a specially designed ventilation fan facility. At the highest volumetric flowrates tested, the flapped blades all produced higher pressures than the baseline...

... are predicted at three reference positions above the propeller for comparison with the experimental data: The amplitudes of the dominant components corresponding to the first, second, and third blade passing frequencies were satisfactorily predicted. It is noted that the maximum difference of pressure...

...Jesús Manuel Fernández Oro; José González; Katia M. Argüelles Díaz; Francisco Israel Guerras Colón Modern designs for centrifugal pumps consider flow unsteadiness as a main concern. The averaged impact of blade to blade structures and impeller-tongue or impeller-diffuser interactions is considered...

... admission as compared with full admission. Thus, an experiment was conducted in a linear cascade apparatus having a partial admission region in order to investigate the effect of partial admission on a blade row. The admission region was formed by a spouting nozzle installed at the inlet of the linear...

... evolved due to interaction between rotor blades and the distorted sector, especially near the trailing edge of the distortion screen. The presence of a strong mode was observed under both co- and counter-rotating inflow distortions. With throttle ramping, stall inception occurs through long and short...

... the purge cavity flow ejected downstream of the stator blade row at three flow regimes: subsonic M 2 = 0.73 , transonic M 2 = 1.12 , and supersonic M 2 = 1.33 . Experimental static pressure measurements were used to calibrate the computational model. The main flow field-purge flow interaction is found...

... in the blade passage, producing shedding vorticity in the downstream passage-flow. The passage-flow separation and the downstream volute flow, which is also affected by the passage-flow separation, have a higher impact on flow losses than the blade leading edge separation. If the gap size is not selected...

..., free-wake is used for wake simulation. The present free-wake describes the inboard vortices as well as the tip vortices of the blade. At each time step, the free-wake provides inflow and outflow conditions of the boundary of the Eulerian domain, and the Euler solver is used for solving the flow field...