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Ryu, Yun-Seon;Kim, Yoon-Seok;Callec, Philippe
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2002.11b
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- pp.166-171
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- 2002
The transmission loss coefficient is very important acoustic property in parallel with absorption and acoustic impedance categorizing the acoustical materials, which can control the acoustical problems. At the same time, the transmission loss coefficient is a key parameter to choose the optimum material for the analysis of acoustical characteristics of material using SEA(Statistical Energy Analysis). In this paper, the transmission loss coefficient measurement system using 4-microphone impedance tube is proposed, based on the idea calculating the full transfer matrix of the acoustical sample to test. The theoretical background and measurement system are introduced, and finally the measurement results are verified.
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Yunseon RYU;Yoon-Seok KIM;Philippe CALLEC
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2002.11a
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- pp.323.1-323
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- 2002
The transmission loss coefficient is very important acoustic property in parallel with absorption and acoustic impedance categorizing the acoustical materials, which can control the acoustical problems. At the same time, the transmission loss coefficient is a key parameter to choose the optimum material for the analysis of acoustical characteristics of material using SEA(Statistical Energy Analysis). In this paper, the transmission loss coefficient measurement system usiong 4-microphone impedance tube is proposed, based on the idea calculating the full transger matrix of the acoustical sample to test. The theoretical backgroung and measurement system are introduced, and finally the measurement results are verified.
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Lee, Dong-Won;No, Hee-Cheon;Song, Chul-Wha;Jeong, Moon-Ki
- Proceedings of the Korean Nuclear Society Conference
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- 1999.05a
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- pp.124-124
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- 1999
An ultrasonic method is developed for the measurement of the two-phase mixture level in the reactor vessel or steam generator. The ultrasonic method is selected among the several non¬nuelear two-phase mixture level measurement methods through two steps of selection procedure. A commercial ultrasonic level measurement method is modified for application into the high temperature, pressure, and other conditions. The calculation method of the ultrasonic velocity is modified to consider the medium as the homogeneous mixture of air and steam. and to be applied into the high temperature and pressure conditions. The cross-correlation technique is adopted as a detection method to reduce the effects of the attenuation and the dif.JUsed reflection caused by suface fluctuation. The waveguides are developed to reduce the loss of echo and to remove the effects of obstructs. The present experimental study shows that the developed ultrasonic method measures the two-phase mixture level more accurately than the conventional methods do.
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김윤석;류윤선
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2003.05a
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- pp.658-661
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- 2003
The transmission loss coefficient is very important acoustic property in parallel with absorption and acoustic impedance categorizing the acoustical materials, which can control the acoustical problems. At the same time, the transmission loss coefficient is a key parameter to choose the optimum material for the analysis of acoustical characteristics of material using SEA(Statistical Energy Analysis). In this paper, the transmission loss coefficient measurement system using 4-microphone impedance tube is proposed, based on the idea calculating the full transfer matrix of the acoustical sample to test. The theoretical background and measurement system are introduced, and finally the measurement results are verified.
PDF