Performance Analysis of Hydraulic Engine Mount by Using Bond Graph Method

This paper presents an analytical modeling and performance analysis of the hydraulic engine mount by using bond graph method, which is becoming more common in the industry for engine vibration and noise control. It is well known that the hydraulic engine mount can provide excellent frequency and amplitude response characteristics compared to the conventional elastic rubber type one. Numerous study has been attempted up to now to explain the complex dynamic performance characteristics of this mount through a variety of analytical methods but it is not yet fully understood. In the present study, the bond graph design model, having an analytical simplicity and clarity, have been developed to analyze and predict the design performance of a “sandwich type” hydraulic engine mount with a spiral inertia track and free decoupler specifically designed for an in-line gasoline engine in order to control and reduce the high amplitude low frequency engine vibration and noise in the frequency range 1 - 50 Hz in particular. To investigate the reliability of the present developed methodology the dynamic response spectra results from the bond model such as the dynamic stiffness and the loss angle are validated with the experimental data over 1-50 Hz and 1-100 Hz frequency range. The bond graph method developed in the study had shown excellent agreements with the experimentals over the cases investigated. The present study results has shown that the bond method has an excellent applicability for the analysis and prediction of hydro engine mount performance if the dynamic system can be properly modeled.