节能轴支架的作用原理设计方法和叶剖面优化

Design Method and Profile Optimization of Energy Saving Shaft Strut

介绍了节能轴支架的作用机理、设计方法和叶剖面的优化。节能轴支架的作用机理与桨前固定导轮相似 ,但设计要比桨前固定导轮简化 ,并要兼顾轴支架自身的作用和要求。文中详细给出了轴支架的布置形式和在船模试验中获得的显著节能效果。试验结果证明把轴支架的两支臂设计成有约 1 0°的收缩角可增大节能轴支架的预旋作用 ,从而增大节能效果 ,使轴支架的节能效果达约 1 2 %。空泡试验和激振力测量结果表明 ,把Eppler的翼型势流设计方法设计翼型与解 N-S方程进行流场分析相结合 ,用层流型高升阻比翼型优化节能轴支架是成功的 ,能有效地降低轴支架的阻力和推迟空泡初生 ,从而有利于节能轴支架在高速船上推广应用。

The working mechanism, design method and profile optimization of energy saving shaft strut (ESSS) are present in this paper. The working mechanism of the ESSS is similar to the fixed guide vane (FGV) in front of the propeller, and the design of the ESSS must be simplified compared with the FGV, but the requirement of the shaft strut itself must be satisfied. The location and orientation of the struts and its energy saving effectiveness obtained in ship model experiments are present in detail in the paper as well. It is shown that the pre swirl action would be enhanced with the convergence angle being about 10° of the two struts of the shaft, and the energy saving effect of the ESSS may be enhanced to about 12%. The cavitation experiment of the ESSS and propeller exciting vibration measurement show that the optimization is successful of the profile of the ESSS with the high lift to drag ratio hydrofoil, which is achieved by combining the potential theory of the Eppler′s wing section design method with the analysis for the fluid field by solving N S equation. In this way the resistance of the ESSS would be reduced effectively and the inception of the cavitation would be delayed significantly. Thus the ESSS may be applied to the highspeed ship rapidly. The sea trail show that the design of the ESSS is successful.