Design and Analysis of Dual Pressure Probes for Predicting Turbulence-Induced Vibration in Low Velocity Flow

Abstract

Measuring highly turbulent fluid flow is challenging, especially in cases where the turbulence intensity exceeds acceptable limits for hotwire anemometry techniques. Using fast response pressure probes is an effective and well documented turbulence measurement method; however, there is little literature about pressure probes capable of measuring turbulence in low mean velocity air flows (0-12 m/s). Also lacking in the literature is a complete method of using pressure probe measurements to predict turbulence-induced vibration. In this paper the design and analysis of two highsensitivity pressure probes is discussed. It will be shown how measurements with these probes are used to develop a statistically derived turbulent fluid forcing function. This function will then be combined with an analytical structural dynamics model such that not only the modal RMS displacements, but also the modal displacement power spectral density plots can be predicted for a given structure. The pressure probe design, turbulence measurement techniques, and both the statistical and analytical models will be validated with experimental results. The results shown in this paper are for a case study performed with a single cantilever exposed to turbulent cross-flow.