Examining the Effect of Flow Reversal on Seven-Hole Probe Measurements
01 Dec 2003-AIAA Journal (American Institute of Aeronautics and Astronautics (AIAA))-Vol. 41, Iss: 12, pp 2460-2467
TL;DR: In this article, a seven-hole pressure probe is rotated in yaw by 360 degrees and rules are formulated to determine if the probe is facing the right direction for data acquisition.
Abstract: Multihole pressure probes are frequently used to gather e ow data, sometimes in highly three-dimensional e ow. If the e ow is reversed, no method currently exists for determining whether the multihole probe is facing the right direction for data acquisition, and that the e ow is as such. A seven-hole probe is rotated in yaw by 360 deg, and rules are formulated to determine if a seven-hole probe is in a reversed e ow. The current study allows seven-hole probes to be used for gathering data in steady reversed e ows and gives an indication whether a pressure probe is insufe cient for the measurement instrument, as in the case of highly recirculating unsteady turbulent e ows. An application of the technique thus developed is also given.
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Cites background from "Examining the Effect of Flow Revers..."
...The aerodynamic research group at the University of New South Wales is heavily engaged in developing diagnostic [4-21] and various flow control [21-49] and simulation methodologies [50-53] to produce energy efficient solutions [54-63]....
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TL;DR: In this article, the authors investigated the relationship between surface roughness and skin friction drag and the time interval between aircraft exterior cleaning and found an optimum time interval for cleaning an aircraft.
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33 citations
References
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18 Jan 1978
Abstract: : In many complex flow fields such as those encountered in turbomachines, the experimental determination of the steady-state, three-dimensional characteristics of the flow field are frequently required. If space limitations or other considerations make nulling techniques impractical, five- hole probles in a non-nulling mode can be employed. However, this application requires complete three-dimensional calibration data which are not usually supplied by commercial vendors. Presented in this paper are the results of programs to calibrate and employ five-hole probes of both angle-tube and prismatic geometries. Included are descriptions of the calibration technique, typical calibration data, and an accompanying discussion of the application or interpolation procedure. Also documented are the variations in the calibration data due to Reynolds number and wall proximity effects. Typical measured data are included and, where applicable, these data are validated by comparison with data obtained using other types of velocity measuring instrumentation.
178 citations
01 Jan 1978
TL;DR: In this article, the results of programs to calibrate and employ five-hole probes of both angle-tube and prismatic geometries are presented, along with typical calibration data, and an accompanying discussion of the application or interpolation procedure.
Abstract: : In many complex flow fields such as those encountered in turbomachines, the experimental determination of the steady-state, three-dimensional characteristics of the flow field are frequently required. If space limitations or other considerations make nulling techniques impractical, five- hole probles in a non-nulling mode can be employed. However, this application requires complete three-dimensional calibration data which are not usually supplied by commercial vendors. Presented in this paper are the results of programs to calibrate and employ five-hole probes of both angle-tube and prismatic geometries. Included are descriptions of the calibration technique, typical calibration data, and an accompanying discussion of the application or interpolation procedure. Also documented are the variations in the calibration data due to Reynolds number and wall proximity effects. Typical measured data are included and, where applicable, these data are validated by comparison with data obtained using other types of velocity measuring instrumentation.
92 citations
TL;DR: In this paper, the calibration of a non-nulling, conical, seven-hole pressure probe over a large range of flow onset angles is described, and the calibration procedure is based on the use of differential pressures to determine the three components of velocity.
Abstract: This report describes the calibration of a non-nulling, conical, seven-hole pressure probe over a large range of flow onset angles. The calibration procedure is based on the use of differential pressures to determine the three components of velocity. The method allows determination of the flow angle and velocity magnitude to within an average error of 1.0° and 1.0% respectively. Greater accuracy can be achieved by using high quality pressure transducers. Also included is an examination of the factors which limit the use of the probe, a description of the measurement chain, an error analysis, and a typical experimental result. In addition, a new general analytical model of pressure probe behavior is described and the validity of the model is demonstrated by comparing it with experimentally measured calibration data for a three-hole yaw meter and a sevenhole probe.
91 citations
TL;DR: In this paper, a method to extend this range by avoiding singularity is developed allowing calibration of a five-hole probe up to much larger angles of pitch and yaw, which can be successfully extended to angles of up to ±75°.
80 citations
TL;DR: In this paper, the effects of Reynolds number, Mach number, and turbulence on the calibrations of commonly used types of five-hole probe are discussed, and the results confirmed the existence of two distinct Reynolds number effects.
Abstract: The effects of Reynolds number, Mach number, and turbulence on the calibrations of commonly used types of five-hole probe are discussed. The majority of the probes were calibrated at the exit from a transonic nozzle over a range of Reynolds numbers (7 × 10 3 < RE < 80 × 10 3 based on probe tip diameter) at subsonic and transonic Mach numbers. Additional information relating to the flow structure were obtained from a large-scale, low-speed wind tunnel. The results confirmed the existence of two distinct Reynolds number effects. Flow separation around the probe head affects the calibrations at relatively low Reynolds numbers while changes in the detailed structure of the flow around the sensing holes affects the calibrations even when the probe is nulled
79 citations