Pitot pressure measurement in high enthalpy expansion tubes

Abstract

This report has investigated the use of a new bar gauge design in order to replace previous iterations of bar gauges and pitot pressure probes for use within UQ's expansion tube facilities.Preliminary hammer calibration testing on different arrangements of the bar gauge showed that the response remained almost constant regardless of shielding, no shielding or different clamping arrangements, varying by only a maximum of 14.59%. It was also concluded that the ratio of strain gauge output to hammer input remained almost constant for the entire test time, and that a calibration factor taken at the 50µs surrounding the peak of the signal will yield the most accurate result. It was determined that due to this reason, deconvolution was not necessary because the response could be characterised using a constant value, known as the calibration factor.