동적 소음저감 기법을 적용한 차량용 소음기가 엔진 성능에 미치는 영향에 대한 연구

김철호(Chul-Ho Kim),백은석(EunSeok Baek),방미연(Miyeon Bang),류호준(Hojun Ryu),이종진(Jongjin Lee),정상훈(Sang-Heon Chung) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

The purpose of this study is on the development of a muffler system which controls the noise and static pressure drop of the exhaust gas of an automobile engine with the concept of the dynamic control method. The control the noise and pressure resistance of the muffler system, the muffler system is designed with two rotating impellers installed in the muffler cavity. Compared to a conventional muffler that has baffles and connecting pipes in the muffler chamber, new concept of the muffler system named Dyna-muffler, has two rotating impellers installed into the muffler chamber separated into two cavities. Each rotor has 6 blades and it acts as a moving baffle absorbing kinetic and pressure energy of the high-pressure, high-speed exhaust gas from the engine. From the experiments, it was found that the pressure resistance of the Dyna-muffler is quite similar to the conventional static muffler in the normal engine operating range. To understand the performance of the Dyna-muffler on the engine efficiency and output power, the engine dynamometer experiments will be conducted.

자동차 배기 소음 저감을 위한 소음기

김병삼 ( Byoung Sam Kim ) 한국환경기술학회 2008 한국환경기술학회지 Vol.9 No.2

자동차 엔진은 환경오염의 주 원인중 하나이기 때문에 전 세계적으로 배기 가스로 인한 피해를 최소화하기 위한 기술이 필요하다. 특히, 배기가스는 자동차 소음기로 배출되고 배기소음은 주변 환경에 매우 유해하다. 배기소음을 저감하기 위하여 자동차 소음기는 최적으로 배출 효율을 가질 수 있도록 설계되어야 한다. 본 연구에서는 배기가수 소음, 소음분포 특성, 배기가스의 압력과 온도에 대하여 공냉 환상형 자동차 소음기의 온도를 변화시키면서 조사하였다. 자동차 소음기의 주파수 해석으로 부터 소음분포는 1,000~2,000Hz 대역이고, 소음저감은 환상 온도에 영향을 받고 있음을 알 수 있었다. Internal combustion engine is the main source of environmental pollutants and therefore advanced technology is required to reduce harmful elements from the exhaust gases all over the world. Especially, when the exhaust gas is released from the automotive muffler, exhaust noise has many bad influence on the surrounding environment. In order to reduce the exhaust noise, it is necessary that automotive muffler must be designed for best exhaust efficiency. The sound insulation room was installed for the analysis of an acoustics characteristics of the noise from automotive muffler, in this study. Exhaust gas noise, noise distribution characteristics, pressure and temperature of exhaust gas were investigated with the change of annulus temperature of air cooled annulus automotive muffler and cooled annulus automotive muffler. The following results were obtained with this study. From the frequency analysis of automotive muffler, high noise distribution was observed in the range 100~2000Hz. It means that the noise in this range has an dominate influence for the overall noise. Noise reduction of automotive muffler was affected by the temperature of annulus. It is caused the result that the high temperature and pressure of exhaust gas are changed lower by the drop of annulus temperature. The tendencies of noise, the temperature and pressure of exhaust gas are similar to the performance curve of engine. Exhaust gas pressure is determined by the revolution per minute of engine and affected by the cooling performance of automotive muffler.

자동차 배기 소음 저감을 위한 환상형 소음기

김병삼 ( Byoung-sam Kim ),김형두 ( Hyung-doo Kim ) 한국환경기술학회 2014 한국환경기술학회지 Vol.15 No.3

자동차 엔진은 환경오염의 주 원인중 하나이기 때문에 전 세계적으로 배기가스로 인한 피해를 최소화하기 위한 기술이 필요하다. 특히, 배기가스는 자동차 소음기로 배출되고 배기소음은 주변 환경에 매우 유해하다. 배기소음을 저감하기 위하여 자동차 소음기는 최적으로 배출 효율을 가질 수 있도록 설계되어야 한다. 본 연구에서는 배기가수 소음, 소음분포 특성, 배기가스의 압력과 온도에 대하여 공냉 환상형 자동차 소음기의 온도를 변화시키면서 조사하였다. 자동차 소음기의 주파수 해석으로 부터 소음분포는 1,000~2,000Hz 대역이고, 소음저감은 환상 온도에 영향을 받고 있음을 알 수 있었다. Internal combustion engine is the main source of environmental pollutants and therefore advanced technology is required to reduce harmful elements from the exhaust gases all over the world. Especially, when the exhaust gas is released from the automotive muffler, exhaust noise has many bad influence on the surrounding environment. In order to reduce the exhaust noise, it is necessary that automotive muffler must be designed for best exhaust efficiency. The sound insulation room was installed for the analysis of an acoustics characteristics of the noise from automotive muffler, in this study. Exhaust gas noise, noise distribution characteristics, pressure and temperature of exhaust gas were investigated with the change of annulus temperature of air cooled annulus automotive muffler and cooled annulus automotive muffler. The following results were obtained with this study. From the frequency analysis of automotive muffler, high noise distribution was observed in the range 100~2,000Hz. It means that the noise in this range has an dominate influence for the overall noise. Noise reduction of automotive muffler was affected by the temperature of annulus. It is caused the result that the high temperature and pressure of exhaust gas are changed lower by the drop of annulus temperature. The tendencies of noise, the temperature and pressure of exhaust gas are similar to the performance curve of engine. Exhaust gas pressure is determined by the revolution per minute of engine and affected by the cooling performance of automotive muffler.

고성능 일체형 자동차 소음기를 장착한 배기계 설계

정수진(Soo-Jin Jeong),강우(Woo Kang),김영태(Young-Tae Kim),이점주(Jeom-Joo Lee) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper has been focused on the development of integrated automotive muffler system to meet getting more stringent sound quality target. Typically, muffler system consists of resonator and main muffler. The many varieties in exhaust pipe routing and the flexibility in muffler design make it possible to design an exhaust system to deliver tailpipe sound for specific sound quality requirement. In recent, it is strongly recommended that the function of resonator be merged into that of main muffler due to severe space limitation of underbody. The main objective of the paper is to study the effects of various geometrical parameters on the muffler performance. This work has succeeded in eliminating resonator without loss of muffler performance. This work has also investigated the effect of diameter of hole, geometries of pipes and location of muffler on the sound quality.

삽입관이 있는 확장형 소음기에서의 기류음 감소

강웅(Woong Kang),김형진(Hyung Jin Kim),성형진(Hyung Jin Sung) 대한기계학회 2009 大韓機械學會論文集B Vol.33 No.2

Turbocharger has been widely used in many passenger cars in application with diesel engines because of high power and fuel efficiency. However, flow-induced noise (whoosh or hissing noise) which is generated within a compressor during its operation at marginal surge line can deteriorate noise characteristics. Hissing noise excitation is associated with the generation of turbulence within the turbocharger compressor and radiated through the transmission path in a turbocharger system. In this study, a expansion muffler with lids is devised and installed in the transmission path to reduce the hissing noise. Acoustic and fluid dynamic characteristics for the muffler are investigated which are related to the unsteadiness of turbulence and pressure in the turbocharger system. A transfer matrix method is used to analyze the transmission loss of the muffler. A simple expansion muffler with lids is proposed for the reduction of high frequency component noise. Turbulence simulation is carried out by a standard k ?ε model. An optimal design condition of the muffler is obtained by extensive acoustic and fluid dynamic analysis on the engine dynamometer with anechoic chamber. A significant reduction of the hissing noise is achieved at the optimal design of the muffler as compared with the conventional muffler.

고성능 일체형 자동차 소음기를 장착한 배기계 설계

정수진(Soo-Jin Jeong),강우(Woo Kang),이점주(Jeom-Joo Lee),김태훈(Tae-Hun Kim) 한국자동차공학회 2009 한국 자동차공학회논문집 Vol.17 No.4

This paper has been focused on the development of integrated automotive muffler system to meet getting more stringent sound quality target. Typically, muffler system consists of resonator and main muffler. The many varieties in exhaust pipe routing and the flexibility in muffler design make it possible to design an exhaust system to deliver tailpipe sound for specific sound quality requirement. In recent, it is strongly recommended that the function of resonator be merged into that of main muffler due to severe space limitation of underbody. The main objective of the paper is to study the effects of various geometrical parameters on the muffler performance. This work has succeeded in eliminating resonator without loss of muffler performance. This work has also investigated the effect of diameter of hole, geometries of pipes and location of muffler on the sound quality.

K1계열 전차에서 소음기 장착에 의한 소음 특성

고형일 ( Hyong-ill Ko ),김민환 ( Min-hwan Kim ) 한국환경기술학회 2018 한국환경기술학회지 Vol.19 No.2

전차는 기동력과 화력, 궤도의 굉음을 바탕으로 적에게 공포감을 주어 위협을 가하는 것이 장점이자 특성이다. 그러나 평시에 소음으로부터 민원이 발생되어 제한적 훈련을 할 수 밖에 없다. 또한, 전차를 운용하는 승무원은 지속적으로 소음과 진동에 노출되어 스트레스가 가중되고 있다. 이를 해소하기 위해 엔진 소음기를 개발하여 K1전차 엔진의 배기가스 출구에 소음기를 설치하여 장착전과 장착후의 소음을 비교하여 저감 정도를 측정하였다. 그 결과 미 장착차량에 비해 장착차량은 엔진 공회전시에는 최대6 dB(A), 주행 중일 때 10 dB(A) 감소하였다. 이에 따라서 엔진 소음기 보급 방안을 검토하였고 이 연구가 전차 주변 소음 환경과 승무원 근무환경 개선에 이바지하는데 기여할 것이다. Army tank’s thundering noise, in addition to its mobility and firepower, is an essential characteristic of the weapon and poses a formidable threat to the enemy. However, in time of peace, the noise induces complaints from the neighbouring civilians near the training grounds, which serves to limit the extent of the forces' training. Also, the stress level of the crewmen may rise due to their constant exposure to noise and vibration during maneuver. In order to resolve such problem, a muffler was introduced to the engine, and the noise level was measured and compared to that of the tank without a muffler. A plan to install mufflers was reviewed, and the effect of mufflers on the noise level experienced by crewmen was analyzed. A tank with a muffler has been shown to be less noisy by up to 6dB(A) idling, and 10dB(A) while driving. Installation of muffler is expected to contribute to the improvement of the crewmen’s working environment.

터보 차져 디젤 엔진에서의 기류음 감소를 위한 연구

강웅(Woong Kang),김형진(Hyung Jin Kim),성형진(Hyung Jin Sung) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

Turbocharger has been widely used in many passenger cars in application with diesel engines because of high power and fuel efficiency. However, flow-induced noise (whoosh or hissing noise) which is generated within the compressor during its operation at marginal surge line can deteriorate noise characteristics. Hissing noise excitation was associated with the generation of turbulence within the turbocharger compressor and radiated through the transmission path in turbocharger system. In this study, a sharp-edged reactive-type muffler was devised and installed in the transmission path to reduce the hissing noise. Acoustic and fluid dynamic characteristics for the muffler were investigated which is related to the unsteadiness of turbulence and pressure in turbocharger system. A transfer matrix method was used to analyze the transmission loss of the muffler. Simple expansion muffler with extended tube of the reactive type is proposed for the reduction of high frequency component noise. Turbulence computation was carried out by a standard k ? ε model. An optimal design condition of the muffler was obtained by extensive acoustic and fluid dynamic analysis on the engine dynamometer with anechoic chamber. A significant reduction of the hissing noise was achieved at the optimal design of the muffler as compared with the conventional turbocharger system.

연료전지 자동차의 공기 공급계용 흡기 소음기의 최적 설계

김의열(Euiyoul Kim),이영준(Youngjoon Lee),이상권(Sangkwon Lee) 한국자동차공학회 2012 한국 자동차공학회논문집 Vol.20 No.5

Fuel cell electric vehicles have some noise problems due to its air processing unit which is required to feed the ambient air into the fuel cell stack. Discrete-frequency noises are radiated from a centrifugal blower due to rotor-stator interaction. Their fundamental frequency is the blade passing frequency, which is determined by the number of rotor blades and their rotating speed. To reduce such noises, multi-chamber perforated muffler has been designed. In this paper, in order to improve the transmission loss of a perforated muffler, the relationship between the impedance model of a perforated hole and its noise reduction performance is studied, and the applicability of a short-length perforated muffler to air processing unit of fuel cell system is described using acoustic simulation results and experimental data. The acoustic velocity vector across the neck of a perforated hole is very important design factor to optimize the transmission of an intake muffler. The suggested short-length perforated muffler is effective on discretefrequency noises while keeping the volume of intake muffler minimized.

머플러에 유입되는 배기가스의 유동 압력에 관한 수치해석

이중섭(Chungseub Yi),최석천(Seukcheun Choi),서정세(Jeongse Suh),정한식(Hanshik Chung),정효민(Hyomin Jeong),배태열(Taeyeol Bae) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This study represents Numerical study on the fluid flow characteristics of exhaust gas into the motorcycle muffler. Numerical analysis with Computational Fluid Dynamics(CFD) was carried out to investigate the exhaust gas that flow into the motorcycle muffler. The STAR-CD S/W used for the three dimensional steady state CFD analysis in a muffler. The Navier-Stokes Equation is? solved with the SIMPLE method with a general Cartesian coordinates system. RNG k-e and MARS(Monotone Advection and Reconstruction Scheme) were used for turbulence model and convection term, respectively.