Shock Tube Pressure Transducer Calibration System

This paper describes the characterisation of the dynamic response of a range of pressure transducer systems. The transducers were subjected to virtually instantaneous pressure step inputs in the National Physical Laboratory’s shock tube facilities. The magnitudes of these pressure steps were derived from ideal gas theory, with prior commissioning tests having been performed to demonstrate the theory’s validity in this application. The results demonstrate a significant variation in response obtained from various combinations of transducer, instrumentation settings, and mounting arrangement.

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High-precision in situ measurement of speed of sound in hydraulic systems

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651819862719 ◽

2019 ◽

Vol 234 (3) ◽

pp. 299-313

Author(s):

Nigel Johnston

Keyword(s):

High Precision ◽

Speed Of Sound ◽

Pressure Transducer ◽

In Situ Measurement ◽

Frequency Domain Method ◽

Hydraulic Systems ◽

Mean Flow ◽

Transducer Calibration ◽

Mean Flow Velocity

An existing ISO standard frequency-domain method for measurement of speed of sound in a hydraulic pipeline is enhanced and extended in this article to include in situ measurement of pressure transducer calibration factors. Transducer mounting stresses are shown to cause variations in the calibration factors, and the proposed method can be used to eliminate these uncertainties, consequently improving the accuracy of the speed of sound. 95% confidence ranges in the speed of sound of less than ±0.1% have been achieved, and such high precision cannot be achieved by other practical methods. The method can also been extended to estimate viscosity and mean flow velocity, but accuracy is less good. Novel time-domain versions of the method are introduced. These may be valuable for real-time monitoring, and changes in speed of sound or calibration factor can be tracked with minimal delay. Some examples showing the effect of sudden aeration are presented; a sudden drop in speed of sound is apparent.

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A Computer-Controlled Pressure Standard

Journal of Fluids Engineering ◽

10.1115/1.2822006 ◽

1999 ◽

Vol 121 (1) ◽

pp. 210-212

Author(s):

Othon K. Rediniotis

Keyword(s):

Pressure Transducer ◽

Pressure Range ◽

High Accuracy ◽

Wind Tunnel Testing ◽

Dual Use ◽

Pressure Source ◽

Subsonic Wind Tunnel ◽

Pressure Standard ◽

Computer Controlled ◽

Transducer Calibration

The operating principles, as well as the technical aspects of the implementation of a new computer-controlled pressure standard are presented. The instrument can have dual use: either as a pressure source or as a pressure sensor. The device is intended mostly for use in problems where small differential pressures are of interest, i. e., 0–2.5 KPa and high accuracy is desired. Such a pressure range encompasses, for example, most of the pressure measurement applications in subsonic wind-tunnel testing. The device interfaces to a PC and is ideal for fully-automated pressure transducer calibration applications. The accuracy of the pressures produced or measured by the device is 0.08 percent F. S. (Full Scale).

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Measurement of Strong Shock Pressure

Shock and Vibration ◽

10.1155/1997/684909 ◽

1997 ◽

Vol 4 (5-6) ◽

pp. 403-409

Author(s):

Hajime Takada ◽

Daisuke Fujimaki ◽

Takao Tsuboi

Keyword(s):

Shock Tube ◽

Pressure Transducer ◽

Shock Absorber ◽

Transfer Functions ◽

Strong Shock ◽

Shock Pressure ◽

Pressure Transducers ◽

Pressure Peak

This paper deals with measurement of a strong shock pressure like an imploding detonation of over 1 GPa which cannot be measured directly with currently available commercial pressure transducers. After the transfer functions of three kinds of materials were measured using a shock tube, Teflon was selected as a shock absorber. As an example of pressure beyond the limit of the pressure transducer, we tried to measure pressure at the center of an imploding detonation. From this measurement, we could estimate the pressure peak of about 1.7 GPa.

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