カドワキ　レン   Ren Kadowaki   門脇　廉    所属   追手門学院大学  理工学部 機械工学科    職種   准教授
発表年月日	2017/11
発表テーマ	Liquid Viscosity Evaluation using Ultrasonic Pulse
会議名	The 17th Asian Pacific Vibration Conference
学会区分	国際学会
発表形式	その他
国名	中華人民共和国|中国
開催地名	南京航空航天大学（南京市）
開催期間	2017/11/13～2017/11/15
発表者・共同発表者	Ren Kadowaki,Naoki Otsubo,Takumi Inoue,Kazuhisa Omura
概要	The purpose of this study is development of a new viscosity evaluation method. We focus on ultrasonic pulse that is transmitted in the target liquid. The liquid viscosity is evaluated through attenuation of the ultrasonic pulse. As the first step, we tried to evaluate the viscosity of some types of mineral oil, whose viscosity were already known. We observed the two pulses that were transmitted in the mineral oil in a test container as shown in figure 1. Comparing the two reflected pulses in frequency domain, spectra of the attenuation in the oil were obtained. To calculate the viscosity of the oil, the theoretical relationships between the viscosity and the attenuation was essential. We performed a numerical simulation of pulse propagation with a lumped mass model as shown in figure 2. The relationships between the damping coefficients and the attenuation were elucidated from this numerical simulation. The damping coefficients were identified for the simulated pulse to resemble the experimental results in their attenuation. In the results, the oil viscosity that was over 100 mPas was evaluated using the experimental and theoretical results.