http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
평판요소 방사효율을 이용한 원통형 구조물 음향방사파워 산출에 관한 연구
한승진(Seungjin Han),강명환(Myunghwan Kang),배수룡(Sooryong Bae),정우진(Woojin Jung) 한국소음진동공학회 2016 한국소음진동공학회 학술대회논문집 Vol.2016 No.4
This study investigates an efficient method to estimate the underwater radiated noise of submerged circular cylindrical structures. The underwater radiated noise is estimated from the measured velocity and the calculated radiation efficiency of the structure surface. The estimation of total acoustic radiation power are in a good agreement with the measurement results for the mid-high frequency range. However, the estimation of radiation directivity does not match well.
접수 원통형 구조물의 표면 진동속도를 이용한 총 방사음향파워 계산
한승진(Seungjin Han),이종주(Jongju Lee),강명환(Myunghwan Kang),배수룡(Sooryong Bae),정우진(Woojin Jung) 한국소음진동공학회 2014 한국소음진동공학회 학술대회논문집 Vol.2014 No.10
Most naval underwater weapon system can be simplified to a circular cylindrical structure which has vibrating machineries inside. In order to predict efficiently the total acoustic radiation power of cylindrical structure, surface velocity is measured and radiation efficiency of surface element is calculated. Then, they are substituted to the surface pressure in the simplified Helmholtz integral equation which assumes acoustic far-field and plane-wave approximation at the surface. Surface velocity and total acoustic radiation power for a submerged cylinder are measured in water-tank. In this example, it is found that total acoustic power output obtained from the prediction is in good agreement with that of measurement in mid-high frequency range.
다중가진을 받는 수중 원통구조물의 방사효율에 대한 수치해석
강명환(Myunghwan Kang),이종주(Jongju Yi),한승진(Seungjin Han),배수룡(Sooryong Bae),정우진(Woojin Jung) 한국소음진동공학회 2014 한국소음진동공학회 학술대회논문집 Vol.2014 No.10
This study is on acoustic radiation efficiency of a tiffened cylindrical model in watermulti-excitation with phase difference using commercial numerical program ABAQUS and SYSNOISE. When the stiffened cylindrical model is under multi-excitation with phase difference, the surface vibration field is variated with phase difference of excitation. By this different surface vibration field, the acoustic radiation efficiency is also variated with phase difference of excitation.
수중반사파 환경에서의 근접음장 홀로그래피 적용에 대한 오차 고찰
이종주(Jongju Yi),강명환(Myunghwan Kang),한승진(Seungjin Han),정현주(Hyunjoo Jeong),배수룡(Sooryong Bae),정우진(Woojin Jung) 한국소음진동공학회 2014 한국소음진동공학회 논문집 Vol.24 No.12
Nowadays, it is required for naval ships to estimate 3D underwater radiated noise pattern in all direction at peak frequencies of hull vibration for the reduction of being detected and doing the effective operation. For this purpose, the numerical method has to be developed to calculate 3D underwater radiated noise pattern with experimental data. It is very difficult to obtain the experimental data for the real ship. Alternative to get the experimental results is to use NAH(near-field acoustic holography) in acoustic tank with experimental model. Application of NAH in acoustic tank for the experimental model needs some investigation of reflection wave from the wall of the acoustic tank and unmeasured zone of the experimental model due to the supporting structure for it. In this study, the effect of reflection wave in the acoustic tank and unmeasured area of the experimental model when using the NAH was investigated with experiment and numerical model. From these, it is known for the error due to reflection wave can be reduced when the distance between the measurement plane and source is being shorten. Also, unmeasured area of the experimental model gives rise to some error in the estimation of the far-field acoustic pressure.
위상차를 갖는 다중 가진 시 구조물의 방사효율 특성 해석
강명환(Myunghwan Kang),이종주(Jongju Yi),한승진(Seungjin Han),배수룡(Sooryong Bae),정우진(Woojin Jung) 한국소음진동공학회 2014 한국소음진동공학회 논문집 Vol.24 No.12
Acoustic radiation efficiency is one of the important factors in the prediction of underwater radiated noise of ships. A ship has much equipment to operate successful mission in a ship. Most of equipment is running simultaneously as multi-excitation and becomes the source of underwater radiated noise. In many cases of multi-excitation, phase difference between multi-excitation is not considered. Because vibration response under multi-excitation is the vector sum of each single excitation, acoustic radiation efficiency based on surface velocity field can be affected by phase of excitation. In this study, acoustic radiation efficiency of a plate on air and a stiffened cylindrical model in water under multi-excitation with phase difference is investigated.
수중실험을 통한 원통구조물의 3차원 수중방사소음 패턴 산출기법 분석
이종주(Jongju Yi),강명환(Myunghwan Kang),한승진(Seungjin Han),정현주(Hyunjoo Jeong),오준석(Junseok Oh),배수룡(Sooryong Bae),정우진(Woojin Jung),서영수(Young Soo Seo) 한국소음진동공학회 2014 한국소음진동공학회 논문집 Vol.24 No.11
In this study for the prediction of 3D underwater radiated noise pattern, a comparison between the proposed method(DHIE, Discrete Helmholtz Integral Equation) and the 3D underwater radiated noise calculation results using the measurement of near-field acoustic pressure data is performed. The near-field acoustic pressure in water is measured for the calculation of the far-field radiated noise pattern and the far-field acoustic power. Also the vibration field of the underwater structure is measured in simultaneously. Using the total far-field acoustic power and the vibration field on the surface of the structure, the proposed method(DHIE) can predict the underwater radiated noise pattern of the far-field The predicted results show the reasonable agreement within about 5dB comparing with the experiment result.