Modelling and Analysis of Propeller Blade

Abstract

Fiber reinforced composites are finding wide spread use in naval applications in recent times. Ships and under water vehicles like torpedoes, Submarines etc., these weapons require propeller to drive the vehicle. In general the propeller will be used as propulsions and it also used to develop significant thrust to propel the vehicle at its operational speed. which are designed for moderate and deeper depths require minimization of structural weight for increasing payload, performance/speed and operating range for that purpose Aluminum alloy casting is used for the fabrication of propeller blades In current years the increased need for the light weight structural element with acoustic insulation, has led to use of fiber reinforced multi layer composite propeller. The present work carries out the structural analysis of a CFRP (carbon fiber reinforced plastic) propeller blade which proposed to replace the Aluminum propel blade. In addition propeller is subjected to an external hydrostatic pressure on either side of the blades depending on the operating depth and flow around the propeller also result in differential hydrodynamic pressure between face and back surfaces of blades. These hydrodynamic pressure takes as a single resultant load act at 1/3 part of the blade. The propeller blade is modeled and designed such that it can with stand the static and dynamic load distribution and finding the stresses and deflections in static analysis for both isotropic and orthotropic materials. In dynamic analysis free vibration (modal analysis) analysis for both isotropic and orthotropic materials. This thesis work basically deals with the modeling and design analysis of the propeller blade of a ship for its strength. A propeller is complex 3D model geometry. Which requires high end modeling CAD software is used for generating the blade model in CATIA V5 R19. This report consists of brief details about Fiber Reinforced Plastic materials and the advantages of using composite propeller over the conventional metallic propeller. This project concentrates on the metal and composite strength analysis of the propeller blade carried out by using the finite element method. By using ANSYS12.0 software static, modal were carried out for both isotropic and orthotropic material. In this work two different types of ship propeller i.e. Aluminum, Composite, were studied using FEM techniques. .