| Project |
CORCOMPA |
| Research Area |
Aero-engine unsteady flows and aeroelasticity |
| Principal Investigator(s) |
M. Imregun |
| Institution(s) |
- Imperial College London, UK
- Rolls-Royce plc, UK
|
Abstract
Aero-engine compressors deliver a large quantity of air at high
pressure. From an efficiency viewpoint, it is desirable to operate them
at the highest possible pressure ratios but such operating points are
inherently unstable because of their close proximity to undesirable
aerodynamic phenomena of stall and surge. Rotating stall is a localÂ
instability where reduced flow rate gives rise to flow separation and
results in the formation of stall cells. These cells begin to rotate
around the annulus and hit the blades, thus causing high vibratory
loads. Surge is a global instability in which flow reversal occurs
throughout the machine, causing high transient stresses in the
blading. Deficiencies in understanding the exact mechanisms and a lack
of modelling methodology prevent the determination of the dynamic loads
and the ensuing blade response. Therefore, current designs are based on
safe margins where the bladerow spacing is not optimum. The overall aim
of the project is not only to understand the rotating stall and surge
mechanisms and the links between them, but also to prove the
feasibility of the large-scale modelling approach as a design tool.
Here, an application is made to find additional computational resource
to extend the scope of an existing study where a large-scale model of
a typical industrial core-compressor has already been built.
