Effect of Manufacturing Tolerances on Performance of Marine Propellers

制造公差对船用螺旋桨性能的影响

• 批准号: 521668-2017
• 负责人: Qiu, Wei
• 金额: $ 1.82万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=639286
• 关键词: Effect; Manufacturing; Tolerances; Performance; Marine

Propeller cavitation is of major concern for ships since it is the predominant source of propeller-generatednoise and vibration. Very limited efforts have been made to understand the impact of propeller manufacturingtolerances on the propeller performance. The majority of propellers manufactured today are hand-finished fromcastings which are roughly machined using Computer Numerical Control (CNC). Manual grinding of propellersurfaces introduces inaccuracies and deviations from design, which could lead to degradation of propellerperformance in terms of efficiency, cavitation and noise. Ship screw propellers are typically manufactured tomeet the ISO 484 Standard, which specifies the manufacturing tolerances.As the key propeller manufacturer in Canada, Dominis Engineering needs the evidence that the high precisionof hydrodynamic surfaces, which can be achieved by the technology of CNC machining to final form andfinish, improves propeller performance. The investigation into propeller manufacturing tolerances will becarried out using computational fluid dynamics (CFD) simulations. The proposed research will focus on 2-DCFD simulations of a full-scale modified NACA 66 section, considering the variations in geometry (chordlength, camber and thickness) due to manufacturing tolerances.The outcomes of the project will enable Dominis to develop improved processes of propeller manufacturing interms of efficiency of production and high precision for reduced noises and vibrations as well as increased fuelefficiency. It will also enable Dominis to further support the Canadian Shipbuilding Strategy and Canada'sglobal competiveness in marine propeller manufacturing, which will ultimately benefit the Canadian economy.

螺旋桨空泡是螺旋桨产生的噪声和振动的主要来源，因此是船舶的主要问题。在了解螺旋桨制造公差对螺旋桨性能的影响方面所做的努力非常有限。今天制造的大多数螺旋桨都是手工精加工的铸件，这些铸件使用计算机数字控制(NC)进行粗略加工。螺旋桨表面的手工研磨会带来设计上的误差和偏差，这可能会导致螺旋桨在效率、气蚀和噪声方面的性能下降。船用螺旋桨的制造通常符合ISO 484标准，该标准规定了制造公差。作为加拿大的主要螺旋桨制造商，Dominis Engineering需要证据表明，通过数控加工到最终成形和精加工技术可以实现高精度的流体动力表面，提高了螺旋桨的性能。螺旋桨制造公差的研究将使用计算流体力学(CFD)模拟进行。拟议的研究将集中于全尺寸修改的NACA 66截面的2-DCFD模拟，考虑到由于制造公差而导致的几何形状(弦长、曲面和厚度)的变化。该项目的结果将使Dominis能够开发改进的螺旋桨制造工艺，以提高生产效率和高精度，减少噪音和振动，并提高燃料效率。它还将使多米尼斯能够进一步支持加拿大造船战略和加拿大在海洋螺旋桨制造方面的全球竞争力，这最终将使加拿大经济受益。