非定常螺旋桨水动力升力面预报

本文基于格林定理和薄翼假计,导出一种升力面离散涡分布法来求解螺旋桨非定常水动力。在本方法中,附着涡和面源分布在桨叶拱弧面上,涡格和控制点的弦向分布形式吸收了Lan的准连续法的特点,非定常的尾涡面上布置了具有时间记忆性的泄出涡。本文在考虑了尾涡收缩的同时,还计入了桨叶梢涡分离。采用时域迭代法求解非定常问题得到时域解,利用谐调分析可进一步得到频域解。作者编制了本方法的计算程序,计算结果令人满意。

Unsteady Hydrodynamics Prediction of Propellers with A Lifting Surface Method

Based on the Green's formula and the assumption of the propeller blade's thin sections, a lifting surface method of propellers with the vortex lattice and equal source panel distributions on the mean camber surface has been introduced for the prediction of unsteady propellers hydrodynamics in this paper. In the method, the chordwise distributions of the vortices and the control points on the mean camber surface of the blade are chosen in the same manner as in the Quasi-Continuous Method developed by Lan 1 ], and the shed time-remembering vortices from thetrailing edge as well as the free vortices are arranged on the trailing vortex wake according to ke-Ivin's theorem of the conservation of vorticity. Not only the wake contraction but also the tip vortices separation has been taken into account. For solving the unsteady problem, a time step iteration scheme is adopted to get the solutions in time region, to which the frequency region solutions can also be obtained by applied the Fourier analysis method. The calculation code of the method has been develop by aulthor, and the calculated results are satisfied.