Hull vibration is the vibration generated by the sailing ship due to various reasons. 90% of the vibration on the ship comes from the pulsating pressure of the propeller, which can generate the stern vibration, superstructure vibration and local vibration. Especially in the area above the propeller, the propeller pulsation pressure often causes local structural resonance or forced vibration, resulting in structural fatigue damage or reduced living comfort. It is therefore necessary to reduce the vibrations caused by the pulsating pressure of the propellers. However, in the early stage of the propeller design, it is not convenient to calculate the pulsating pressure of the propeller due to the complexity of the calculation method. It is important to design a software that can quickly estimate the pulsating pressure of the propeller. In the current study, a software for the rapid estimation of the pulsating pressure of propellers is developed by using the empirical formulas with a mixture of QT and MATLAB programming, to discuss the influencing factors and variations of the pulsating pressure. The results show that the shape parameters of the ship section, the type of the ship and the rotation speed of the propeller greatly affect the pulsation pressure of the propeller. It can provide references for the ship vibration and noise reduction.

A software has been developed to predict the inherent longitudinal vibration characteristics of the ship shafting. The software is developed using the QT platform, with the core solver written in MATLAB and the solution algorithm using the Holtz method. The results are compared and verified with the simulation results of ANSYS and the longitudinal vibration calculation results of an actual shafting system. On this basis, the developed software is used to discuss the variation of the longitudinal vibration characteristics of the shafting under different shafting properties. The results show that the properties affecting the inherent longitudinal vibration characteristics of the shafting mainly include the crank radius, crank thickness, longitudinal stiffness of thrust bearings and material elastic modulus. The relevant research results can provide references for the vibration and noise reduction of the ship shafting.