1. 연 사 : 고승환 교수


서울대학교 공과대학 조선해양공학과 초빙교수


2. 제 목 : Turbulent Flow Noise Estimates for Submarine Hull Arrays


3. 일 시 : 1999년 10월 21일 (목) 16:00


4. 장 소 : 301동 1512호


5. 내 용 :


This talk consists of two parts. First, an introduction of sonar parameters which are related by the sonar equations for naval operation will be presented. There are many types of noise interference that arises in the sonar design. Among those noises, a self noise that originates from the pressure fluctuations underneath the turbulent boundary layer is a great concern when a submarine is in motion. Second, techniques for reducing these turbulent boundary layer pressure fluctuations using wave number filters, such as a finite hydrophone, an array of hydrophones, and a layer of elastomer will be discussed. The turbulent wall pressure spectrum that represents the flow excitation function is the Corcos model to fit a realistic estimate at the low wavenumber region. The occurrence of the convective ridge wavenumber is estimated using a convective flow speed as a function of frequency. Numerical results calculated for various hull array configurations will be presented to discuss their performances.


6. 문 의 : 최해천 교수 (☏ 880-8361)