3Transmission Measurement Committee. Measurement of gas by multipath ultrasonic meters [S]. Washington, D. C.. American Gas Association, 1998.
4WALSH J T. A report of acoustic transit time accuracy field work performed in North America [C]//The 5th International Conference on Hydraulic Efficiency Measurements, Luceme, Switzerland, 2004: 21-29.
5DRENTHEN J G, BOER G. The manufacturing of ultrasonic gas flow meters [J]. Flow Measurement and Instrumentation, 2001, 12.- 89-99.
6WALSH J T. ASME PTC 18-2002 Hydraulic turbines and pump-turbines[S]. New York: ASME, 2002.
7VOSER A. CFD-Calculations of the protrusion effect and impact on the acoustic discharge measurement accuracy[DB/OL]. (1996-06-28)[2010-08-30]. http: //www. ighem.org/Paper 1996/IGHEM 1996_35.pdf.
8LOWELL F, SCHAFER S, WALSH J. Acoustic flowmeters in circular pipes: Acoustic transducer and conduit protrusion effects in discharge measurement [DB/OL]. (1998-08-20)[2010-08-30]. http://www.ighem.org/ Paper 1998flQHEM 1998_05.pdf.
9RENALDAS R. Investigation of the flow velocity profile in a metering section of an invasive ultrasonic flowmeter [J]. Flow Measurement and Instrumentation, 2006, 17: 201-206.