This paper focuses on the development of a complete nonlinear model of a hydraulic engine mount. The model is capable of capturing both the low- and high-frequency behaviour of hydraulic mounts. The results presented here provide a significant improvement over existing models by considering all nonlinear aspects of a hydraulic engine mount. Current laboratory findings have been used to evaluate nonlinear parameters and hyper-elastic modelling in ANSYS has been used to find complex stiffness. Also switching mechanism of decoupler has been applied. The comprehensive transfer function of linear system has been obtained, by a simultaneous defining of state parameters, scalar output variable and state space matrices. Results indicate two zones of unsatisfactory in system behaviour which correspond to the real system performance and experimental data. The measured responses of the mounts to loading at various frequencies and amplitudes are compared to the predictions of the mathematical model. The comparisons generally show a very good agreement, which corroborate the nonlinear model of the mount. It is felt that this work will help engineers in reducing mount design time, by providing insight into the effects of various parameters within the mount.

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