... for hydrodynamically preloaded three-pad radial AFB in the hot section. It is found that both bearing and rotor should be provided with cooling air to maintain the temperature of both the rotor and top foil below 300 °C. It is also found that the higher thermal contact resistance between the rotor and hot impellers...

...Wei Xu; Tong Wang; Chuangang Gu; Liang Ding The holed casing treatment is a new type of casing treatment that has self-adaptability for a centrifugal compressor with unshrouded impeller. It was demonstrated experimentally and numerically that both the stall margin and the choked margin...

... induced by a different choice of the total temperature measurement section. With this goal in mind, the study focused on the analysis of a commonly found discrepancy between the measurements at the impeller outlet section and at the stage exit section. Based on the experimental data collected...

... and dynamic) in an oil-free turbo blower with a 75 kW (100 HP) rate power at 30,000 rpm. The turbo blower provides a compressed air with a pressure ratio of 1.6 at a mass flow rate of 0.92 kg/s, using a centrifugal impeller installed at the rotor end. Two GFJBs with a diameter of 66mm and a length of 50 mm...

...Dara Childs 17 10 2007 09 11 2007 23 11 2010 compressors computational fluid dynamics impellers pumps rotors The authors are to be commended for an interesting demonstration of computational fluid dynamics (CFD) methods in the analysis of rotordynamic forces...

...J. Jeffrey Moore; David L. Ransom; Flavia Viana The energy industry depends on centrifugal compressors to produce, process, reinject, and transport many different gases. Centrifugal compressors use one or more impellers to impart momentum to the flowing gas and, thereby, produce an increase...

...Albert Kammerer; Reza S. Abhari Centrifugal compressors operating at varying rotational speeds, such as in helicopters or turbochargers, can experience forced response failure modes. The response of the compressors can be triggered by aerodynamic flow nonuniformities such as with diffuser-impeller...

...Manoj K. Gupta; Dara W. Childs An analysis is developed for a compressible bulk-flow model of the leakage path between a centrifugal-compressor impeller’s shroud and its housing along the impeller’s front and back sides. This development is an extension of analyses performed first by Childs (1989...

... field stability problems are much more expensive to diagnose and correct. Current industry standards and tools for the prediction of impeller destabilizing forces are based on empirical methods that, to date, have served fairly well for systems with reasonable stability margins. However, as stability...

... for both compressors and turbines. This experimental study aims to gain insight into forced response vibration at resonance for a radial compressor. For this purpose, a research impeller was instrumented with dynamic strain gauges and operated under resonant conditions. Modal properties were analyzed using...

.... In turbocharging applications, forced response cannot be avoided due to a number of factors, i.e., change in speed, inlet bends, or obstructions in the flow field. This study aims to quantify the damping parameter for the lightly damped blades of a centrifugal compressor. The impeller geometry is typical...

...Hong-Won Kim; Jong-II Park; Seung-Hyup Ryu; Seong-Wook Choi; Sang-Hak Ghal An examination of the condition of the flow leaving the impeller exit kinetic energy often accounts for 30–50% of the shaft work input to the compressor stage; for energy efficiency, it is important to recover as much...

... stable on the test stand and in the field. Confidence has been established in predicting the excitation forces from seals and bearings, but impeller aerodynamic excitation forces continue to be a challenge. While much attention is paid to impellers from an aerodynamic performance point of view, more...

...M. Mansour; N. Chokani; A. I. Kalfas; R. S. Abhari The time-dependent relative entropy field at the impeller exit of a centrifugal compressor is measured. This study is part of a broader effort to develop comprehensive measurement techniques that can be applied in the harsh environment...