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Optimum knock sensor location through experimental modal analysis of engine cylinder block
Technical Paper
2011-32-0637
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English
Abstract
The knock sensor is provided on an engine cylinder block to detect abnormal engine combustion (knocking) and to provide feedback to engine control unit (ECU). The ECU then modifies the engine input and avoids knocking. A commonly used knock sensor is an accelerometer that detects cylinder wall vibration and estimates knocking of the engine. Selecting the location of a knock sensor in many cases involves a challenging trial and error approach that depends upon the measurement of the knock signal at many locations on engine structure. However, a cylinder block exhibits many structural resonances. Thus, a large vibration signal at the surface of cylinder block can be either due to knocking of the engine or due to the resonances of the cylinder block structure because of normal excitation forces. Hence, this conventional method does not always yield reliable results. The aim of the work reported in this paper is to experimentally determine the inherent dynamic characteristics of a cylinder block and to combine this with a calculation of the fundamental knock frequency and, thus, to identify the optimum location for the knock sensor.
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Citation
Chaudhary, Y., Walsh, S., Prakash Singh, O., and Subramoniam, C., "Optimum knock sensor location through experimental modal analysis of engine cylinder block," SAE Technical Paper 2011-32-0637, 2011.Also In
References
- “Engine structure vibration” Lalor, N 11 th Annual course on Engine noise and vibration control University of Southampton September 1992
- “Investigations on influence of engine block design features on noise and vibrations” Busch, G. Maurell, R. Meyer, J. Vorwerk, C. SAE Technical Paper series 911071
- “A basic study on reduction of cylinder block vibrations for small diesel cars” Honda, Yasuhiro Wakabayashi, Katsuhiko Kodama, Tomoaki Kihara, Ryoji SAE Technical Paper series 2000-01-0527
- “Combustion knock sensing: Sensor selection and application issues” Dues, Steven M. Adams, Joseph M. Shinkle, George A. SAE Technical Paper series 900488
- “An experimental study on knock sensing for a spark ignition engine” Jang, Seok-Hyung Lee, Yong-Gil Oh, Taek-Yul Park, Kyoung-Suk SAE Technical Paper series 931902
- “Engine knock control via optimization of sensor location” Forbes, James W. Carlstrom, Kevin R. Graessley, William J. SAE Technical Paper series 951237
- “Determination of knock sensor location on a heavy-duty natural gas engine” Soylu, Seref Van Gerpen, Jon SAE Technical Paper series 971705
- “Optical investigation of knocking location on S.I.-engines with direct injection” Topfer, G. Reissing, J. Weimar, H.-J. Spicher, U. SAE Technical Paper Series 2000-01-0252
- “Computing the optimum knock sensor locations” Bengisu, Turgay SAE Technical Paper series 2002-01-1187
- “Prediction of knock sensor locations with background noise” Shi, Yucheng SAE Technical Paper series 2005-01-2554
- “Modal Analysis” He, Jimin Fu, Zhi-Fang 2001 Butterworth Heinemann 0750650796
- “Structural Testing, Part 2: Modal analysis and Simulations” Ole Dossing Bruel Kjaer