Date of Award

9-2022

Degree Name

MS in Mechanical Engineering

Department/Program

Mechanical Engineering

College

College of Engineering

Advisor

Russell V. Westphal

Advisor Department

Mechanical Engineering

Advisor College

College of Engineering

Abstract

The objective of this thesis is two-fold: to analyze the directional calibration of a 3-hole probe in steady flow and to develop a method for the interpretation of measurements recorded with a novel, fast-response Pitot-type probe in unsteady, turbulent flow. Calibration data for the 3-hole probe’s two side ports was taken in the steady, non-turbulent region of a free jet and was evaluated for symmetry. In addition, data that was recorded using one side port in two independent calibration runs was compared to study repeatability. Misalignment was found between the nominally symmetric data sets, which may be the result of geometric probe tip defects or a misalignment of the side ports within -2 to -10 degrees. This misalignment suggested that the two probe ports must both be calibrated. The two data sets compared for repeatability were almost indistinguishable, suggesting that probe alignment was very repeatable over multiple calibration runs. This result implied that only one calibration run may be necessary for a single probe as well as for multiple probes having nearly identical tip geometry. These methods and findings from the 3-hole probe calibration provide useful processes and considerations for the calibration of directionally sensing pressure probes. Regarding the fast-response Pitot-type probe, measurements were conducted using the same free jet as was used with the 3-hole probe. The fast-response probe, which contains a Kulite sensor fitted in the sensing orifice of a Pitot tube, was positioned at incremental centerline locations in the unsteady, turbulent region of the jet flow, and mean and dynamic pressure data were recorded. Measurements were also taken at incremental centerline locations with a standard Pitot tube and a constant temperature hot wire anemometer. The Kulite mean pressure data and standard Pitot tube data were compared directly and agreed well. The hot wire data and a relevant turbulence model was used to generate mean pressure predictions, which correlated reasonably with a slight offset from the Kulite sensor and Pitot probe mean data. Next, the dynamic pressure data from the Kulite sensor was compared with predictions generated by the hotwire data, literature static pressure fluctuation data, and a second relevant turbulence model. In the centerline region where turbulence quantities begin to stabilize, the Kulite sensor data and predictions agreed reasonably well, within 7%. Thus, while not delivering ideal results, the turbulence models used provide a plausible method for the interpretation of the fast-response Pitot-type probe pressure measurements.

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