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Some aspects of the flow in S-shaped diffusing ducts

Published online by Cambridge University Press:  04 July 2016

S. C. M. Yu
Affiliation:
School of Mechanical and Production EngineeringNanyang Technological University, Singapore
E. L. Goldsmith
Affiliation:
Formerly Royal Aerospace Establishment Bedford, UK

Extract

The circular cross-sectional Royal Aerospace Establishment (RAE) 2129 S-shaped intake diffusing duct series, shown in Fig. 1, which has an offset of the inlet and exit centerline of 0·3 and 0·45 of the axial length of the duct, was designed at the RAE (Bedford) and tested at British Aerospace Filton, at low forward speeds (freestream Mach no. range from 0 – 0·2 but a range of duct inlet Mach numbers up to choking speeds) in the last two decades to fulfil the objectives of collecting systematic experimental data on engine face pressure recovery, total pressure flow distortion and wall static pressures for computational fluid dynamics validation. Some of the measurements have been presented, as for example, by Willmer, Brown & Goldsmith. The measurements from one version of Model 2129 (the 0·3 length offset S-duct geometry) have been used to compare with calculated results from a number of CFD programs, as for example, by Anderson, Horton and by the AGARD Working Group 13. The series of comparison also highlight the need for measurements other than the engine face total pressure and wall static pressure which have already been made.

Type
Technical Note
Copyright
Copyright © Royal Aeronautical Society 1994 

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