Recent developments and applications of quantitative laser light sheet measuring techniques in turbomachinery components

• Published in: Measurement science & technology 2000-07, Vol.11 (7), p.1023-1035
• Main Authors: Roehle, I, Schodl, R, Voigt, P, Willert, C
• Format: Article
• Language: English
• ISSN: 0957-0233; 1361-6501
• DOI: 10.1088/0957-0233/11/7/317

Three newly developed quantitative laser light sheet techniques utilizing the scattered light of tracer particles are described in the context of the further development of gas turbine engines. Firstly, a Doppler global velocimetry (DGV) system optimized for time-averaged three-component velocity measurements is presented. The system, which uses a single viewing direction in conjunction with three different illumination directions, enables very accurate velocity measurements. Secondly, a quantitative light sheet (QLS) technique for quantitative mass fraction measurements in mixing processes is described. To apply the technique, the inflow of the mixing experiment must consist of at least two separate flows, one of which can be seeded while the other remains unseeded. DGV and QLS results obtained from experimental investigations in model combustion chambers are presented. Thirdly, a method named tracer-based shock visualization (TSV) is described which is capable of determining the shape and structure of shock waves in transonic flows by analysing the sudden increase of flow density across a shock. Results taken in a transonic axial compressor are presented. (Original abstract - amended)