Abstract The surface-piercing propellers (SPPs) are a specific type of supercavitating propellers that have higher efficiencies at high advance speeds. The SPPs operate on a free surface, so due to the ventilation and air suction into the water, the pressure of the suction surface of the blade approaches atmospheric pressure. Given the importance of better understanding this phenomenon, in this research, the formation and development of ventilation in an SPP5.74 5-blade SPP is numerically investigated by defining proper geometrical and physical parameters. The finite volume method (FVM) has been implemented to numerical modeling and simulating the free surface carried out by the volume of fluid (VOF) two-phase model. The numerical results have compared with the experimental data with similar conditions due to validating the simulation. Also, the simulations were carried out in six different advance coefficients ranges from 0.44 to 0.94. In the results section, different parameters are introduced, including the length and thickness of the ventilation zone, the influence of the advance coefficient on the physics of the ventilation phenomenon have been evaluated in various propeller radius ratios. The results show that in the suction surface and the points where ventilation starts, the pressure tends to the atmospheric pressure, by reducing the advance coefficient, the thickness, and the length of the ventilation zone increase, in this condition, the ventilation zone moves towards the leading edge. In constant advance coefficients, increasing the radius ratio reduces the thickness and the length of the ventilation zone. In high radius ratios and near the tip of the blade, the ventilation is limited to the trailing edge. Moreover, the analysis of the pressure coefficients shows that in the ventilation zone, the pressure coefficient is zero, while in the other areas, it ranges from 0 to 1. With larger advance coefficients, the areas with the zero pressure coefficient tend towards the trailing edge.

中文翻译：

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影响穿面螺旋桨通风形成和增长的参数的数值研究

摘要 穿面螺旋桨（SPPs）是一种特殊类型的超空泡螺旋桨，在高推进速度下具有更高的效率。SPP在自由表面上运行，因此由于通风和空气吸入水中，叶片的吸力表面的压力接近大气压。鉴于更好地理解这种现象的重要性，在本研究中，通过定义适当的几何和物理参数，对 SPP5.74 5 叶片 SPP 中通风的形成和发展进行了数值研究。有限体积法 (FVM) 已用于数值建模和模拟由流体体积 (VOF) 两相模型执行的自由表面。由于对模拟的验证，数值结果与类似条件下的实验数据进行了比较。还，模拟是在 0.44 到 0.94 的六个不同提前系数范围内进行的。在结果部分，引入了不同的参数，包括通风区的长度和厚度，在各种螺旋桨半径比下评估了提前系数对通风现象物理的影响。结果表明，在吸力面和通风开始点，压力趋向于大气压，通过降低提前系数，通风区的厚度和长度增加，在这种情况下，通风区向前沿。在恒定提前系数中，增加半径比会减小通风区的厚度和长度。在高半径比和叶片尖端附近，通风仅限于后缘。此外，对压力系数的分析表明，在通风区，压力系数为零，而在其他区域，它的范围从0到1。随着超前系数的增大，零压力系数的区域趋向于尾随边缘。