Experimental Aerothermal Study on Internal Jet Engine Structures

Licentiate thesis, 2020

For commercial aviation, one potential gain in efficiency can be found in the jet engine auxiliary modules, such as internal jet engine components. These components have historically largely been overlooked, prioritising units such as turbines or compressors. The publically available information for these auxiliary units is therefore relatively sparse even though they can enable substantial weight reduction and novel synergistic integration. The continuously increased fidelity of modern numerical tools poses a dilemma to the experimentalist. Higher accuracy and resolution are sought, but the accuracy of the experimentalist tools has stagnated.

This thesis summarises instrumentation implemented methods in the Turbine Rear Structure(TRS). For the multi-hole probe and heat transfer measurement via IR-thermography a comprehensive uncertainty analysis and error mitigations are presented.

The work presents a relatively high accuracy of 4% to 6% for the performed heat transfer studies on the outlet guide vane in the TRS. The presented implementation of the multi-hole probe in the TRS provides up to twice as high accuracy compared to conventional installation. Both approaches are general with few geometrical limitations and can be implemented on studies with similar ambient conditions.

Two different Reynolds numbers, several flow-coefficients and three different surface roughness numbers have been investigated and novel results regarding transition location, streamline, heat transfer and loss distribution are presented in the attached papers.