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本文建立了非定常螺旋桨势函数面元法的理论方法和数值方法,发展了相应的计算机程序,采用通过迭代实现的非线性压力库塔条件,计算了一常规桨和一大侧斜桨的桨叶表面非定压力,并与测试结果及人的计算结果进行了比较。 相似文献
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本文给出了螺旋桨周围流场的预报方法及其数值计算结果。本方法以具有涡分布和源汇分布的升力面来构造螺旋桨对流场的状动。升力面取奖叶拱弧面。根据桨叶表面流动不穿透条件解出升力面奇点后,然后再求它们对流场的扰动。敞水螺旋桨的脉动速度计算结果与试验结果吻合良好。 相似文献
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为探究螺旋桨各参数对螺旋桨性能影响关系,从面元法基本方程和面元法边界条件出发,建立螺旋桨参数影响分析的伴随方法.通过分析等压库塔条件,建立了伴随方程,基于伴随方程探究了螺旋桨性能与参数之间的敏感导数求解公式.选择DTMB4381桨作为研究对象,开展螺旋桨推力系数与螺距分布和拱弧分布之间的敏感导数求解,得到不同参数对螺旋桨性能的影响规律.数值结果表明,伴随方法计算得到的敏感导数与传统方法计算结果具有很好的一致性,但伴随方法的计算时间更短,且随着变量个数的增多,伴随方法计算效率的优势越大. 相似文献
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Yoo-Chul Kim Tae-Wan Kim Sangwoo Pyo Jung-Chun Suh 《Journal of Marine Science and Technology》2009,14(2):161-170
We refine the geometry of a propeller by modifying the blade sections to align them with surface streamlines, obtained by
the panel method. Redefinition of the blade sections aligned with the streamlines is provided together with surface modeling
scheme by which model propellers were built. Numerical simulations and open-water tests on models suggest a possible increase
of 1% in propeller efficiency. 相似文献
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Numerical Calculation
of Marine Propeller Hydrodynamic Characteristics in Unsteady Flow by Boundary Element
Method 总被引:2,自引:0,他引:2
In this paper, a low-order potential based on surface panel method is used for the analysis of marine propellers in unsteady flow.A linear propeller wake model is employed and its geometry is assumed to be independent of the time.The calculation in time domain is carried out from a moment when the rotation of the propeller becomes steady instead of from the moment when the rotation strats from stationary condition.At every time step a linear algebraic equation established on a key blade is solved numerically combined with the Kutta pressure conditon.The calculated results by developed code indicate good convergency and effrctiveness of present algotithm for conventional propellers and highly skewed propellers. 相似文献