Respon Getaran Sistem Propulsi Kapal General Cargo 5200 DWT

Abstract

This research has identified the value of natural and excitation frequencies to resonance. This analysis uses the eigenvalue matrix method with mass and stiffness variables to find the natural frequency value that occurs in the propulsion system. The finite element method is also used to compare the natural frequency values obtained mathematically. The excitation frequency of the system is generated due to the rotation of the main engine. From the modelling results, three natural frequency values were obtained, namely 14.2 rad/s, 36.1 rad/s, and 1291.7 rad/s. The resulting excitation frequency consists of five variations of engine rotation, namely 240 rpm, 310 rpm, 347 rpm, 360 rpm, and 459 rpm. The comparison of the excitation frequency with the natural frequency shows that the propulsion system does not experience resonance. The resulting response values are displacement and velocity, where the most significant response occurs at 347 rpm with a deviation of ±0.1345 mm to ±0.3371 mm and a velocity value of ±4.8847 mm/s to ±12.2424 mm/s. Meanwhile, the slightest response occurs at 459 rpm with a deviation range of ±0.0034 mm to ±0.0050 mm and a velocity value of ±0.1634 mm/s to ±0.2382 mm/s. From all the analysis results, the vibration responses are still below the permissible threshold line, and the vibration of the propulsion system is in the acceptable area.