Research on the Effect of Residual Stress to the Measurement of Shaft Power

Abstract

The measurement of shaft power is the main performance parameter for the shipyards and the owners of new ships, it can be measured to assess the working condition of the power system. Therefore, the accuracy of measurement and the reliability of data is particularly important. In this paper, causes of marine shafting macro residual stress were analyzed, and the residual stress finite element model of shaft deformation was established. The FEM model of marine shafting is based on an axial-symmetrical model of the shaft and subjected to a realistic bearing towards the gearbox-end. The FEM model assumes in particular supports at the main bearing in radial and axial direction. The dynamics of the roller elements, inside the bearings will likely contribute to additional residual stress by rigid motion. The shaft power of the marine shafting was measured taking the additional residual stress into account. Simulation and experiment show that the residual stress on the shaft deformation accounts for about 3%, which cannot be ignored. The control of the potential error from residual stress in the process of shaft power measurement is of great significance for improving the shaft power measurement accuracy.