Total-pressure averaging in pulsating flows.A number of total-pressure tubes were tested in a nonsteady flow generator in which the fraction of period that pressure is a maximum is approximately 0.8, thereby simulating turbomachine-type flow conditions. Most of the tubes indicated a pressure which was higher than the true average. Organ-pipe resonance which further increased the indicated pressure was encountered with the tubes at discrete frequencies. There was no obvious combination of tube diameter, length, and/or geometry variation used in the tests which resulted in negligible averaging error. A pneumatic-type probe was found to measure true average pressure and is suggested as a comparison instrument to determine whether nonlinear averaging effects are serious in unknown pulsation profiles.
Document ID
19730027816
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Krause, L. N.
Dudzinski, T. J.
Johnson, R. C. (NASA Lewis Research Center Cleveland, Ohio, United States)