Improving the Performance of Centrifugal Compressors by Flow Recirculation

Abstract

The impeller of a centrifugal compressor is traditionally designed using some formula for only one design point which makes it less efficient in all other situations. This is especially important for compressors not experiencing a constant working condition. To improve the performance at low mass flow rates and retard the surge, an innovative concept is introduced for a centrifugal compressor. In this method pressurized air is injected at the compressor inlet to improve the flow field. With better incidence angle, related losses at off design conditions are minimized and the surge is delayed. This system is designed, modeled and adjusted for providing an optimal flow pattern at the inlet. Its implementation on a compressor has shown an increase of efficiency at low mass flow rates. It has also improved flow pattern in impeller passages and decreased the blade loading near surge condition. It is also shown that the swirl generator system can be fed up from the compressor volute or diffuser, and thus widening the compressor performance map by retarding the surge margin.

Flow Simulation and Model Analysis of Efficiency and Pressure Ratio Behaviors in GT4086 Turbocharger Compressor

“…S.A Mousavi and M. Mojaddam optimized different models of impeller designs by using various algorithms and computational fluid dynamics methods, applied on the GT4082. The results show a significant increase in the pressure ratio, efficiency, and extension of the surge point [23][24][25][26][27][28].…”

Design of Electric Supercharger Compressor and Its Performance Optimization

“…The impeller also has an important impact on the performance improvement of the compressor, so a lot of research work has been carried out by scholars in the design optimization of the compressor [19][20][21][22]. Li et al studied a set of high-speed compressor impellers with different geometries and analyzed the secondary flow model, where the ratio of impeller inlet diameter to outlet diameter has an effect on the impeller flow uniformity, which, in turn, affects the compressor efficiency [23].…”