Особенность воздействия системы автоматики на резонансные режимы гребного вала судна

Abstract

The scientific relevance of the study lies in the fact that it proposes the first ever visual model that simulates the process of joint operation of the marine diesel engine automation system and the ship's propulsion system. The purpose of the study is to analyse the features of the propeller shaft operation in resonant modes of torsional vibrations. The research method of the study is modelling on the VisSim software product. The paper presents a developed model of the ARCH-DMCH complex, which allows for a comprehensive study of the dynamic modes of the ship's propulsion system. It is presented that in the steady state with the simultaneous action of vibration disturbances from the diesel engine and from the propeller, the amplitude of torsional vibrations of the propeller shaft outside the resonance range can durably and significantly exceed the value of the nominal torque of the diesel engine. The possibility of the occurrence of a resonance of torsional vibrations in the propeller shaft of a ship at a frequency of its rotation outside the forbidden operating range is investigated. It was established that when external perturbations are imposed on one another and vibrations occur, their low frequency can resonate with the natural frequency of the propeller shaft vibration. It was found that for low- and medium-speed diesel engines, the resonance band from the blade frequencies of external excitation must be combined with the critical frequency band of the DMC into one band of forbidden frequencies, since they are located quite close to each other, which is undesirable in the long-term operation of a diesel engine at low rotational speeds of the propeller blade.