Optimized Vibration Isolation in Diesel Generators: The Effect of Stiffness and Damping Coefficients on Vibration Behavior
Abstract
In this study, the vibration behavior of a diesel engine–generator power unit was investigated through numerical simulations. The main objective is to determine the dynamic characteristics of vibrations transmitted from the engine block to the base frame and to improve isolation performance by selecting suitable mount parameter sets. Analyses were carried out in the ANSYS environment under static and dynamic loading conditions. The generator base frame was connected to the ground through vibration mounts modeled as linear spring–damper elements. Five different parameter sets with varying stiffness and damping coefficients were examined. The system’s natural frequency range was identified by increasing the crankshaft’s angular velocity, and deformation distributions on the chassis were evaluated at the operating frequencies of 25 Hz and 50 Hz. Results showed that the system’s natural frequency is approximately 12.46 Hz. At this frequency, mounts with low stiffness and low damping produced the highest base deformation, while at higher operating frequencies, high damping and stiffness mounts caused greater deformation. This behavior aligns with the vibration transmissibility ratio principle—when the operating frequency approaches the natural frequency, deformation increases, whereas greater separation improves isolation. Consequently, a low stiffness–high damping combination was determined to provide optimal performance in reducing vibration amplitudes and transmissibility. These findings emphasize the importance of simultaneously optimizing stiffness and damping parameters in vibration isolation design.
Keywords
Vibration isolation, Natural frequency, Transmissibility ratio, Mount stiffness & damping, Finete element analysis
Supporting Institution
AKSA Generator Industry Inc.
Ethical Statement
This article does not require ethics committee approval.
This article has no conflicts of interest with any individual or institution.
Thanks
We would like to express our sincere thanks to AKSA Generator Industry Inc. for the technical support, laboratory facilities, and dedicated workspace provided during this study. The engineering infrastructure, experimental resources, and knowledge sharing provided by the company were essential to the successful completion of this research.
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