2012 Fiscal Year Final Research Report

Study on Piston Slap -induced Liner Cavitation

Research Project

Project/Area Number	22560227
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Dynamics/Control
Research Institution	Kyushu University
Principal Investigator	OHTA Kazuhide 九州大学, 工学研究院, 教授 (60403929)
Project Period (FY)	2010 – 2012
Keywords	キャビテーション / 内燃機関 / ピストンスラップ
Research Abstract	The internal combustion engine sometimes encounters the cavitation erosion induced by piston slap. The impact vibration between the piston and cylinder liner generates the pressure fluctuation on the coolant side of the liner and leads to occur the cavitation in the case that dynamic pressure falls below its vapor pressure. Authors developed the analytical method to predict the liner vibration caused by the piston slap and the acoustic characteristic of the water coolant passage of the actual diesel engine in vacuum condition was analyzed and compared with the measured result. Moreover, theoretical method to determine the coupled vibratory characteristics of structure and water acoustic field was developed. This method employs Finite Element Method and modal analysis technique. Calculated results of vibro-acoustic characteristics of the rectangular tank were compared with the measured ones and the effect of the heavy fluid loading was elucidated.