船舶艙間振動噪音模擬分析與診斷

Simulation, Analysis and Diagnosis of Cabin Noise and Vibration

鄭凱安(Kai-An Cheng)

指導教授 ： 陳琪芳

共同指導教授 ： 洪振發

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201704337

摘要

由於國際海事組織(The International Maritime Organization, IMO)通過了船舶艙間噪音之相關法規，船舶內部無論是機艙或是住艙等空間皆有噪音限制，故艙間噪音已經是不可忽略的問題。本研究對海洋研究船三號進行振動與噪音的量測分析，針對船上之主要噪音源(主機與發電機)進行量測，同時依照船舶行駛中不同航速與主輔機開關狀態做各別的探討，可得到不同情況下的主輔機振動噪音資料。利用頻譜與倒頻譜的方法與振動噪音傳遞的特性分析出機艙各振動源特徵，並且在不同的艙間量測噪音與振動，透過頻譜找出與噪音相關性最高之振動源，用以診斷出艙間噪音源。從機艙與住艙的比對結果可得知海研三號之二號發電機對於機艙噪音影響較大，而一號電機與住艙相關性較高，柴油主機之振動和噪音較發電機低。除了以實驗資料相互比對之外，本研究同時利用有限元素分析軟體COMSOL Multiphysics模擬出機艙與住艙聲場。由實驗量測與模擬比對可得知噪音模擬曲線與量測值相當接近，兩間住艙的噪音模擬結果與實驗平均誤差在2 dB以內，而機艙平均誤差為2.5 dB。本研究從機艙的振動與噪音量測到住艙的噪音頻譜比對，配合不同艙間的噪音模擬，建立一套艙間振動噪音的診斷與噪音預估的模式。

關鍵字

船舶振動與噪音 ； 艙間噪音 ； 有限元素法

並列摘要

Ship noise have been noticed recently, because noise limitations in the ship, including the cabin or accommodation, have enforced to be international regulations by International Maritime Organization. In this study, we analyzed the vibration and noise of Ocean Researcher III and focused on figuring out the main source. In order to discuss the different rotational speed of the noise source, we used accelerometers and microphones at different rotating speed of engine and turned on and off the generator at the same time. Analyzing the spectrum and cepstrum to extract the feature of vibration, we discussed that the correlation between the noise in the cabins and the vibration of the engine. The result of the measurement showed that generator No.2 had a great effect on the engine room, the accommodation was affected by the generator No.1, the vibration and noise of diesel engine was less effect than the generator. In addition to the experimental data, we also simulated the acoustic field of different cabin by the finite element method software (COMSOL), and analyzed the difference between the simulation and measurement. According the measurement of the vibration and noise in the cabin, the noise spectrum in the accommodation, and the comparison with the simulation of different cabins, the noise curve of the measurement was close to the curve of simulation. The error of two noise curve in the cabin was less than 2 dB, and the error in the engine room was less than 2.5 dB. In conclusion, this study could apply to predict and diagnose the vibration and noise of the ship.

並列關鍵字

ship vibration and noise ； cabin noise ； finite element method

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