Sökning: "rotating stall"
Hittade 5 avhandlingar innehållade orden rotating stall.
1. Flow instabilities in centrifugal compressors at low mass flow rate
Sammanfattning : A centrifugal compressor is a mechanical machine with purpose to convert kineticenergy from a rotating impeller wheel into the fluid medium by compressingit. One application involves supplying boost air pressure to downsized internalcombustion engines (ICE). LÄS MER
2. Numerical investigation of the flow and instabilities at part-load and speed-no-load in an axial turbine
Sammanfattning : Global renewable energy requirements rapidly increase with the transition to a fossil-free society. As a result, intermittent energy resources, such as wind- and solar power, have become increasingly popular. However, their energy production varies over time, both in the short- and long term. LÄS MER
3. Operating conditions impact on flow and acoustics in turbocharger compressors
Sammanfattning : Fluid machines are an integral part in energy conversion with applications from pumps, fans, propellers, compressors and turbines. In the automotive industry, turbochargers are commonly employed to counteract the effect of engine downsizing. LÄS MER
4. Centrifugal compressor flow instabilities at low mass flow rate
Sammanfattning : Turbochargers play an important role in increasing the energetic efficiency andreducing emissions of modern power-train systems based on downsized recipro-cating internal combustion engines (ICE). The centrifugal compressor in tur-bochargers is limited at off-design operating conditions by the inception of flowinstabilities causing rotating stall and surge. LÄS MER
5. Measuring with pressure sensitive paint in time-varying flows
Sammanfattning : Increasingly tougher legislation on internal combustion engine emissions drives the development towards smaller engines with higher efficiency where an important component is the gas-exchange system and especially the turbocharger. The flow in the gas-exchange system is inherently pulsating and unsteady and the present thesis aims at investigating if and how pressure sensitive paint (PSP) can be used for internal unsteady flows of relevance for engine applications. LÄS MER