Current trends on intermediate pressure, axial compressors designs for aeroengine applications demand to extend their operation envelope into low Reynolds number regimes, of the order of 105 based on the real chord and inlet velocity (Re). In this range, a very limited open experimental database on profile performance can be found. Furthermore, in order to propose high efficiency designs for this regime, it is critical to determine and to understand the profile behaviour with respect to different operating parameters. In this work, a detailed experimental study of a proposed high efficiency, intermediate pressure compressor aerofoil has been carried out, both for design and off-design flow incidences, in the range 1.5 · 105 < Re < 3.5 · 105,. The experimental facility is a low-speed linear cascade where different boundary suction strategies have been implemented to optimize the flow periodicity and to minimize pressure gradient perturbations induced by end-wall secondary flow development, in an effort to ensure high quality, 2D passage flow evolution both at design and significant off-design incidences. High resolution total pressure loss and LDV traverses performed at different streamwise locations have been carried out to describe the flow evolution. The characterizations performed at close to nominal incidence give a profile loss dependence on the Reynolds number that exhibits two clearly differentiated ranges, with the lower one exhibiting a higher profile loss dependence on the Reynolds number. At large off-design incidences, the profile loss coefficient practically becomes independent of the Reynolds number, rapidly increasing as the incidence is increased. In both cases physical arguments and scaling laws based on the experimental evidence are proposed to explain the profile behavior. RANS and URANS based CDF simulations have been also conducted, showing their ability and limitations to capture the experimentally observed aerofoil behavior.

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