• Title, Summary, Keyword: 노킹

Search Result 50, Processing Time 0.046 seconds

Knocking and engine damage (노킹과 엔진손상)

  • 전광민;이종화
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.14 no.4
    • /
    • pp.1-5
    • /
    • 1992
  • 1. 노킹의 발생. 2. 노킹 발생 이후의 압력파. 3. 노킹 발생과 엔진 손상 부위. 4. 엔진손상 방지책.

  • PDF

Analysis of Cavity Resonances caused by Knocking in Chamber of High Power Engine (고출력 엔진에서 연소실 내의 노킹음에 의한 공진현상 분석)

  • Lee, Du-Gon;Jang, Seok-Hyung;Yi, Chong-Ho;Park, Kyung-Suk;Jun, Kye-Suk
    • The Journal of the Acoustical Society of Korea
    • /
    • v.11 no.4
    • /
    • pp.31-35
    • /
    • 1992
  • Cavity resonances are caused by combustion such as the rapid of pressure rise that occurs from knock in high power gasoline engines. These resonances generally occur at frequencies greater than 5KHz. Analysis of these resonances is important for knock control system design in high power gasoline engines. In this paper, in order to design knock control system for the high power gasoline engine, knock phenomena that occur in chamber were analized theoretically and resonance frequencies of knock signals were predicted. Also, experiments were performed using Soupe x-engine and non-resonance type knock sensor of Bosch co. in Germany. In the result, good agreement was obtained between theoretical prediction and experimental observation.

  • PDF

A Study on the Knocking Characteristics with Various Excess Air Ratio in a HCNG Engine (HCNG 엔진의 공기과잉율 변화에 따른 노킹 특성에 관한 연구)

  • Lim, Gihun;Park, Cheolwoong;Lee, Sungwon;Choi, Young;Kim, Changgi;Lee, Janghee
    • Journal of the Korean Institute of Gas
    • /
    • v.17 no.1
    • /
    • pp.7-12
    • /
    • 2013
  • As emission regulation for vehicle has been reinforced, many researches carried out for HCNG(hydrogen-natural gas blends) fuel to the conventional compressed natural gas (CNG) engine. However, abnormal combustion such as backfire, pre-ignition or knocking can be caused due to high combustion speed of hydrogen and it can result in over heating of engine or reduction of thermal efficiency and power output. In the present study, improvement of combustion performance was observed with HCNG fuel since it can extend a flammability limit. Knocking characteristics for CNG and HCNG fuel were investigated. Feasibility of HCNG fuel was evaluated by checking the knock margin according to excess air ratio. The operation of engine with HCNG was stable at minimum advance for best torque(MBT) spark timing and knock phenomena were not detected. However, it is necessary to prepare higher knock tendency since possibility of knock is higher with HCNG fuel.

Development of Knocking discrimination and Engine balance Correction Algorithm of CRDI Engine ECU (산업용 CRDI 엔진에서 노킹 분석 시뮬레이터 구현 및 OBD-II 진단기 S/W 설계)

  • Kim, Hwa-seon;Jang, Seong-jin;Nam, Jae-hyun;Jang, Jong-yug
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • /
    • pp.369-373
    • /
    • 2012
  • 최근 강화된 국내외의 배출가스 규제 조건을 충족시키기 위해, 사용자의 요구대로 연료의 분사시기와 분사량을 조절할 수 있는 CRDI ECU 제어 알고리즘의 개발이 필요하다. 따라서 본 논문에서는 산업용 CRDI 엔진 전용 ECU에 적용할 수 있는 노킹 판별 및 엔진 밸런스 보정이 가능한 노킹 분석 시뮬레이터를 개발하였다. 개발한 노킹 분석 시뮬레이터의 결과를 OBD-II 표준을 사용하여 차량 위주의 진단기를 개발하여 운전자가 직접 차량을 진단할 수 있는 운전자 중심의 진단 서비스를 제공하고자 한다. 이를 위해 자동차 고장진단 신호 및 센서 출력 신호를 유선시스템과 무선 시스템인 블루투스 모듈을 이용하여 실시간 통신이 제공 될 수 있는 OBD-II 진단기 S/W 설계 방안을 제안함으로써 차량의 연비를 향상시키고, 유해 배출가스의 발생을 최소화하여 엔진 효율성의 개선 방안을 제시하고자 한다.

  • PDF

The Fuzzy Controller for Spark Ignition Engine Knock Control (스파크 점화기관의 노킹제어를 위한 퍼지제어기 개발)

  • Lee, Jae-Hyung;Ham, Yun-Young;Chang, Kwang-Soo;Chun, Kwang-Min
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.21 no.2
    • /
    • pp.223-231
    • /
    • 1997
  • A variety of approaches have been investigated for the application of spark-ignition engine knock control. The control method implemented, here as "Fuzzy Control", has the advantage of not requiring the knowledge of a mathematical model of the controlled object and is more robust and flexible than conventional approaches. Knock control in this study is performed using vibration signal which is measured with accelerometer attached to the cylinder block of a 1498cc four-cylinder spark-ignition engine. The experimental results obtained with this method are compared with those obtained with a knock interval controller and with those of a conventional controller. Those results illustrate better performance in torque than knock interval controller and conventional controller.ontroller.

The Effect of Intake Air Temperature on Knock Characteristics in a Spark-Ignition Engine (흡입 공기 온도변화에 따른 스파크 점화기관의 노킹 특성 변화)

  • 정일영;전광민
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.1 no.1
    • /
    • pp.22-31
    • /
    • 1993
  • Spark-ignition engine knock is affected by engine operating conditions such as engine speed, spark timing and intake air temperature. In this study the effect of intake air temperature on knock characteristics was studied experimentally using a 4-cylinder carburetor spark-ignition engine. The cylinder pressure data at 2000rpm were taken for intake air temperature range of $30^{\circ}C$ to $80^{\circ}C$ with $10^{\circ}C$ interval. And 80 consecutive cycles were taken at each experimental condition. As the same spark timing, as the intake air temperature increased by $50^{\circ}C$, the mean knock intensity increased about 20kPa. This effect corresponds to that of spark timing advance of 3 crank angle degrees.

  • PDF

Measurement and Analysis of Knock for Rapid Throttle Opening in SI Engines (가솔린 엔진에서 급가속 운전시 노킹 측정 및 분석)

  • 이종화;박경석;김현용
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.7 no.9
    • /
    • pp.28-35
    • /
    • 1999
  • In this study, investigation of transient knock characteristics in a spark-ignition engine has been carried out. The universal knock threshold values were found by a DFDD method and a NSDBP method which is a non-dimensional version of the SDBP method. Also modified NSDBP method could be used for transient knock detection. In a commercial ECU , spark timing was retarded from the steady -state spark timing during rapid throttle opening to avoid uncomfortable feeling and knock. Knock usually occurred just after the start of rapid throttle opening when spark timing was set, as values for the steady state condition. We found that air/fuel ratio deeply involved with the knock during transient condition. Due to the difference of initial heat release rate, knock occurred more easily at rich air/fuel ratio than at lean air/fuel ratio.

  • PDF

Method of Decreasing the Deviation of Corrected Engine Torque using Knock Correction Rate in Gasoline Engine Performance Test on Dynamometer (가솔린엔진 대상 성능시험시의 노킹보정률을 사용한 엔진 수정토크의 편차개선)

  • Cho, Yoon-Ho;Kim, Woo-Tai;Bae, Choong-Sik
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.4
    • /
    • pp.1-7
    • /
    • 2008
  • Recent trends of development in small size gasoline engines are both to have higher compression ratio for the purpose of improved fuel consumption and to advance spark timing up to DBL in a low to mid engine speed region for a good acceleration performance of vehicles. However, there occurs the deviation of corrected engine torque results during engine performance test on dynamometer because test conditions influence the onset of knock. Therefore, this research shows the test deviation of corrected engine torque decreases when knock correction rate is used.

Investigation of the Knocking Phenomenon in SI Engines (가솔린 엔진에서의 노킹 현상 해석)

  • Min, Kyoung-Doug
    • Journal of the Korean Society of Combustion
    • /
    • v.5 no.2
    • /
    • pp.29-35
    • /
    • 2000
  • Knock in SI engines causes physical damage to the piston and combustion chamber and lowers the thermal efficiency. The increase in compression ratio which can improve the thermal efficiency and engine performance has been limited by engine knock. So the need of making clear the knocking phenomenon has increased. This paper reviews the methods of knock detection, characterization and prediction of knock with the reduced chemical kinetic modeling.

  • PDF

Investigation of the Knocking Phenomenon in SI Engines (가솔린 엔진에서의 노킹 현상 해석)

  • Min, Kyoung-Doug
    • 한국연소학회:학술대회논문집
    • /
    • /
    • pp.17-23
    • /
    • 2000
  • Knock in SI engines causes physical damage to the piston and combustion chamber and lowers the thermal efficiency. The increase in compression ratio which can improve the thermal efficiency and engine performance has been limited by engine knock. So the need of making clear the knocking phenomenon has increased. This paper reviews the methods of knock detection, characterization and prediction of knock with the reduced chemical kinetic modeling.

  • PDF