A Novel-Double Notch Passive Hydraulic Engine Mount
Tikani, R., Vahdati, N., Ziaei Rad, S.,Heidari, S., Esfahanian, M., “A Novel-Double Notch Passive Hydraulic Engine Mount”, ICA2010, Australia.
Abstract: Passive hydraulic engine mounts are broadly applied in the automotive and aerospace applications to isolate the cabin from the engine noise and vibration. The engine mounts are stationed in between the engine and the fuselage in aerospace applications. In fixed wing turbofan engine applications, the notch frequency of each hydraulic engine mount is adjusted to either N1 frequency (engine low speed shaft imbalance excitation frequency) or to N2 frequency (engine high speed shaft imbalance excitation frequency) at the cruise condition. Since most of today's passive hydraulic engine mount designs have only one notch, isolation is only possible at either N1 or at N2, but not at both. In this paper, a novel double-notch passive hydraulic engine mount design is proposed. The new design consists of two inertia tracks. One inertia track contains a tuned vibration absorber (TVA) where the other one does not. This design exhibits
two notch frequencies, and therefore can provide vibration and noise isolation at two different frequencies. The notch frequencies of the new design are easily tunable and the notches can be placed at N1 and N2 with ease. The new passive hydraulic engine mount design concept and its mathematical model are presented in details and some discussions on the simulation results are also included.