Fracture-life Estimation for Diesel Engines using Vibration Signals

In battle environments, naval vessels operate under the extreme conditions, such as rapid speed fluctuations, sharp turns, and sudden stops. For a high durability of the main engine and reduction gear, flexible couplings and mounts are applied to absorb transient shock. However, in a special condition, the misaligned force and vibration caused by the deformation of the flexible mount and coupling can damage some components of the shaft system. Therefore, a condition-monitoring system is required to check these types of vibrations and forces. Through these monitoring signals, a maintenance plan can be established and the residual useful cycles of the main component of the shaft system can be estimated. This paper describes the fracturing of cylinder blocks of diesel engines caused by high vibrations. Based on the acceleration signals obtained using a recorder black box during a specific operational period, the cumulative damage of the cylinder block from the vibration can be estimated. Therefore, a maintenance plan for the cylinder block based on the cumulative damage is suggested.