建立拖航水槽量測船舶聲納球艏流體噪音與分析技術

Establishing Measurement and Analytical Techniques for Ship Sonar Bulbous Bow Fluid Noise in a Towing Tank

本研究之重點在於建立拖航水槽量測船舶聲納球艏流體噪音與分析技術，做為評估船艏聲納安裝及船型選擇參考。由於國內水槽無論是空蝕水槽或拖航水槽均有機器運轉的背景噪音，而拖航水槽是具備拖航及造波功能，更能貼近實況，惟拖航水槽的背景噪音較多，包括台車噪音、造波機噪音以及水槽自身背景噪音等，在技術上需逐項量測測試，在逐項噪音源分析後再執行複合式拖航與造波試驗量測，以獲取分離噪音所需的噪音頻率及聲壓位準，比較後進而獲得可靠的量測結果。透過本研究整體評估，已成功分離出特定噪音區間，後續可將試驗數據納入設計階段，提供具聲納球艏船型設計之進一步改良參考，以提高聲納探測效能。本研究之結果可以得知，經拆解噪音源分析技術建立，在拖航水槽於特定的中低頻範圍中可執行比較與評估，技術之建立將提供未來不同噸位、不同聲納球艏船型設計時，拖航水槽流體噪音量測與分析技術參考依據。

This study focused on establishing a towing tank measurement and analysis technology for ship sonar bulbous bow fluid noise. The research results serve as a reference for evaluating ship bow sonar installation and the selection of ship bow lines. Domestic ship model test tanks, whether large cavitation tunnels or towing tanks, all have background noise from machine operation. The towing tank has towing and wave-making functions, which are closer to the actual situation. The towing tank measurements have more background noise, including that from the towing trolley, the wave-maker machine, and the background noise of the water tank. These noises need to be measured and recorded individually. After analyzing the noise sources, the results were combined with the towing and wave-making measurements. Then, the results were used to obtain the necessary data for separating those noises. The frequencies and sound pressure levels of those noises were compared to obtaining reliable measurement results. Through the overall evaluation, a noise range was suc-cessfully identified and separated. The measurement data can be incorporated into the design stage to provide a reference for further improvements. The results can be used in the design of ships with sonar bulbous bows to enhance sonar detec-tion performance. It is also evident that, through the establishment of disassembly noise source analysis technology, comparison and evaluation can be performed in a specific mid-low frequency range. The establishment of this technology will provide a technical reference for measuring and analyzing fluid noise in a towing tank when designing various types of sonar bulbous bow ships in the future.