A dynamic model based on the thermoand ‡uidmechanic processes taking place in a centrifugal compressor is validated. The background for this is the need for a energy based model including the rotational speed as a state in order to perform energy based active surge control. The response of the model is compared with experimental results from the Energy Technology Laboratory at Eindhoven Univers...

In order to improve centrifugal compressor performance predictive capability, an improved recirculation loss model in two-zone modeling system is presented in this paper. The new loss model correlates Reynolds number of the impeller with the recirculation loss. Performance prediction by the improved model is carried out on two turbochargers with different sizes based on COMPAL mode of the code ...

Gas turbine inlet fogging and overspray (high-fogging) have been considered the most cost-effective means of boosting a gas turbine’s total power output, especially under hot or dry weather conditions. The result of employing fogging or overspray is indisputably clear − total power output is increased; however, development of the theory and explanation of the phenomena associated with fogging a...

For a 120kW hydrogen fuel cell system, centrifugal air compressor with fixed power of 22kW is designed. Firstly, the theoretical calculation carried out for aerodynamic characteristics ultra-high-speed permanent magnet synchronous motor, an compressor, and foil bearing. Then, prototype trial-produced related test bench built verification. Finally, both simulation results indicate that designed ...

A stage-by-stage wet-compression theory and algorithm have been developed for overspray and interstage fogging in the compressor. This theory and algorithm are used to calculate the performance of an 8-stage compressor under both dry and wet compressions. A 2D compressor airfoil geometry and stage setting at the mean radius are employed. Six different cases with and without overspray have been ...

This paper covers the development of stage-by-stage and parallel flow path compressor modeling approaches for a Variable Cycle Engine. The stage-by-stage compressor modeling approach is an extension of a technique for lumped volume dynamics and performance characteristic modeling. It was developed to improve the accuracy of axial compressor dynamics over lumped volume dynamics modeling. The sta...

For several decades, turboexpander designers have relied on experience and traditional design tools to create their products. Recent advances in CFD (computational fluid dynamics) software and desktop computing power have made it possible for some manufacturers to investigate unique fluid flow fields in routine design applications. In this paper, four case studies of CFD in high performance exp...

Influence of diffuser vane position on dangerous blade vibration due to blade flow interactions at part load operating condition was investigated in a centrifugal compressor. By means of some measurement and analysis techniques a mechanism of interaction between blade vibration and circumferential flow condition in the impeller with vaned diffuser was determined, which is a cause of dangerous b...