A SIMPLIFIED APPROACH TO THE DETERMINATION OF THE HYDRODYNAMIC PARAMETERS OF THRUST BEARINGS IN SHIP PROPULSION SYSTEMS

The article indicates the existing problems of calculating the axial vibrations of ship shafts of diesel power plants. It is noted that these problems are associated with the difficulties of solving hydrodynamic differential equations. The methodology for solving these equations by the finite difference method is considered. A compiled computer program by the help of which multivariate calculations were performed with the assignment of initial data in a random way. The results of these calculations are subjected to approximation processing in order to obtain analytical dependencies for stiffness and damping coefficients. The given approximate formulas are characterized by a simple and logically clear structure. Their presence makes the calculation of axial vibrations of ship shafts more correct and operational. It is established that the stiffness coefficient is a function of only the dimensions of the thrust pad, and the damping coefficient also depends on the rotational frequency of the thrust collar. Special attention is given to assessing the accuracy of the calculation of stiffness and damping coefficients using the proposed formulas. It is shown that the discrepancy between the results of calculations obtained from the solution of integral equations of hydrodynamic and the proposed formulas does not exceed 6 percent.