A Study on the Design and Structural Analysis for Marine Controllable Pitch Propeller Hub

Controllable pitch propeller(CPP) can move blade pitch angle and change vessel's direction without reversing device. There are two types such as collar and trunnion bearings. For the proper design of the CPP system satisfying the requirements of customer, structural analysis and calculation are performed in accordance with classification society requirements. This thesis is focused on the design and structural analysis of two types. In the structural design of hub assembly, the strength and mass of each component of the hub assembly are important factors to determine the accuracy of blade pitch as well as durability of the CPP system. The strengthes of propeller hub, blade bolts and crank pin are evaluated by calculation with using finite element method. The collar bearing type of CPP is a simpler and cheaper solution, therefore CPP of this type is more applicable for commercial vessels. But the trunnion type of CPP has many advantages compared to the collar type of CPP. There are an ability to install up to 7 blades and a smaller dependency from bolt properties. Also the blades arrangement of trunnion type does not need bolts and it has a smaller disk size for the same number of blades compared with the collar type CPP. In this instance, the CPP of trunnion type is an appropriate fit for the naval purposes(explosive shock) and ice breakers. For marine controllable pitch propeller domestically develop, compared collar bearing type assembly with trunnion bearing type assembly by calculation with using finite element method. Crank pin shear stress of trunnion bearing type assembly is a smaller than collar bearing type assembly. Trunnion bearing type assembly is a stronger than collar bearing type assembly. For improved quality and optimized designing of CPP, the structural analysis is need to compare collar bearing type with trunnion bearing type assembly by various methods. Also the results of it's analysis is necessary to choose type of CPP hub and structure mechanism in connection with vessel purpose.List of Table ⅲ List of Figures ⅳ Abstract ⅶ 제1장 서 론 1 1.1 연구의 배경 1 1.1.1 가변피치 프로펠러의 개요 1 1.1.2 가변피치 프로펠러의 현황 2 1.2 연구의 내용 3 제2장 가변피치 프로펠러 허브 어셈블리 설계 4 2.1 개요 4 2.2 허브 어셈블리 설계를 위한 일반적 정의 4 2.3 허브 어셈블리 설계 6 2.3.1 허브 어셈블리의 기하학적 정의 8 2.3.2 블레이드 볼트의 응력 계산 8 2.3.3 베어링 링의 응력 계산 14 2.3.4 크랭크 핀의 굽힘 및 전단 응력 계산 18 제 3장 가변피치 프로펠러 허브 구조해석 22 3.1 칼라 베어링형 허브의 구조해석 22 3.2 트러니언 베어링형 허브의 구조해석 26 제4장 허브 형식별 비교 검토 37 4.1 블레이드 수에 따른 허브 형식별 모멘트 암 관계 37 4.2 허브 형식별 반력 38 4.3 허브 형식별 블레이드 포트간의 구조 차이 39 4.4 허브 형식별 크랭크 핀 전단응력 40 4.5 허브 형식별 블레이드 볼트 비교 40 4.6 허브 형식별 허브내 이중유압관 및 공기방출관 43 제5장 결 론 45 참고 문헌 4