The Journal of the Acoustical Society of Korea

한국음향학회 (The Acoustical Society of Korea)
권호 표지

Measurement of Complex Modulus of Acoustic Materials by Using Transfer Function Method

  • Kim, Hyun-Sil (Acoustics Lab. Korea Institute of Machinery and Materials) ;
  • Kim, Jae-Seung (Acoustics Lab. Korea Institute of Machinery and Materials) ;
  • Kang, Hyun-Joo (Acoustics Lab. Korea Institute of Machinery and Materials) ;
  • Kim, Bong-Ki (Acoustics Lab. Korea Institute of Machinery and Materials) ;
  • Kim, Sang-Ryul (Acoustics Lab. Korea Institute of Machinery and Materials)
  • 발행 : 2002.03.01
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초록

Two improvements are discussed in measurement of the complex Young's modulus of the acoustic materials by using the transfer function method. It is found that the accelerometer misalignment might result in the severe measurement error, particularly in high frequency range. The supporting structure is modified to attach the upper and lower accelerometers along the vertical axis. Secondly, the method fur solving the equation associated with wave model is described. The solution of the lumped mass-spring model is chosen as the starting value for low frequency range, while in the mid and high frequency, the solution to the previous frequency step is used as the initial values. Measurements are done for hard and soft rubber specimens. It is shown that the erroneous peaks in the transfer function, due to the measurement error, cause highly incorrect Young's modulus and loss factors.

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참고문헌

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