Static and Dynamic Analysis of Marine Propeller Blades Using a Customized Finite Element Method

Abstract

Statistical analyses of data from eight different sandstones and shaly sandstone formations show that linear combinations between porosity and clay content explain changes in elastic moduli. The outliers highlight a mineralogy effect on elastic rock properties. The model underestimates all moduli with stiff cements (calcite and pyrite) since it is developed for sandstones with weak cements (clay minerals). Thus, the model can be used for quality checking data and predicting. A customized Propeller blade and hub static and dynamic analysis using a finite element method has been developed. Dynamic analysis results include: natural modes and frequencies of vibration and time history response. The problem of voluminous input data for the finite element method is bypassed, by using an automatic propeller- hub data generation method. Special features of the data generation method are its flexibility in the number and distribution of elements in the chordwise and spanwise directions, allowing thus its straightforward application to usual and unusual (e.g. highly skewed) propeller blade geometries and its capability to accept pressure distributions directly from a lifting surface computer program. Some examples of application of the program to static and dynamic analysis of propeller blades are presented and compared with existing experimental data. Sensitivity analysis of the results with respect to the finite element discretization used is also presented.