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Digital Study of a Stability Analogy

Published online by Cambridge University Press:  04 July 2016

B. S. Thornton
Affiliation:
Honeywell EDP, Sydney, Australia
T. M. Park
Affiliation:
ICT, Bracknell

Extract

An investigation has been made into the stability of compressor blade flutter in separating flow in the presence of external perturbations. The fluttering blade is an example of a hysteretic system governed by a non-linear difference-differential equation for which an analytical approach is not possible and for which the authors originally proposed this new treatment. For design purposes a digital computer has been used to produce stability diagrams under specified conditions including blade torsion. The solution for the response is also available if required. The method involves forming the non-linear feedback analogue to the blade system and which has behaviour governed by the same equation as that studied. The stability is then studied on a digital computer in the presence of small external perturbations by means of a dual input describing function applied to the analogous feedback system with consideration given to the aerodynamic phase lag involved and initially small blade torsional motion.

Type
Technical Notes
Copyright
Copyright © Royal Aeronautical Society 1967

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References

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