气层作用下几何相似滑行艇的阻力换算方法研究

Study on Resistance Calculation Method Between Geometrically Similar Planing Crafts with Air Cavity

通过对有气层时滑行艇总阻力的量纲分析,指出艇型一定的滑行艇气层减阻率为容积傅氏数、无量纲气流量系数、气穴面积分布率以及雷诺数的函数,并可简化为气穴面积分布率与无气层时摩擦阻力与总阻力之比的乘积。提出了几何相似滑行艇之间阻力换算的"计及气穴面积分布率修正的二因次阻力换算法",通过对两条尺度不同、几何相似的滑行艇模型试验,验证了该方法的可靠性。

The dimensional analysis on the total resistance of planing craft with air supply was presented. The results of analysis indicate that the rate of resistance reduction by air cavity to a certain hull form is a function of the volume Froude number, non-dimensionalized air flow rate coefficient, the ratio of air cavity area to wetted surface area without air supply and Reynolds number, and it can be simply expressed as the product of two factors: One is the ratio of air cavity area to wetted surface area without air supply; the other is the ratio of frictional resistance to total resistance without air supply. The two-dimensional resistance calculation method modified by the ratio of air cavity area to the wetted surface area without air supply, for the resistance calculation between geometrically similar crafts with air cavity, was presented, and verified by the results of a series of tests on two geometrically similar models of different size.