海洋污损对船体摩擦阻力影响的预测方法（英文）

Method of Estimating the Effect of Marine Fouling on Frictional Resistance of Ships

海洋污损对船体阻力具有严重的不利影响。文章将海洋污损归类到船体粗糙度的范畴内,基于边界层积分法研究了污损对船体摩擦阻力影响的预测方法。通过对光滑平板摩擦阻力系数的计算验证了积分法的准确性。然后采用积分法对美军FFG-7舰在3种钙质污损状况下的摩擦阻力系数进行了计算,计算结果与国外学者的研究结论吻合得较好,说明了积分法预测污损对船体摩擦阻力的影响具有可行性,且准确性较高。最后将积分法在FFG-7舰的计算结果与1957-ITTC公式及其粗糙度补贴系数△C_f进行了对比,结果表明ITTC提出的△C_f公式不适于表征污损对船体阻力的影响。

Marine fouling has a severe adverse effect on the hydrodynamics of a ship＇s hull. In thispaper, the marine fouling was approached as a type of hull roughness, and the use of the integralmethod in estimating its effect on the frictional resistance of ships was studied. Through the calculationof the friction factor of a smooth surface, the accuracy of the integral method was verified andconfirmed. The integral method was then adopted to calculate the friction factor of a U.S. Navy FFG-7 class ship under three different calcareous fouling conditions, which gave a result consistent withthat from other researchers, indicating the feasibility and accuracy of the integral method in estimatingthe effect of marine fouling on hull resistance. The result using the integral method for a FFG-7ship was compared with result from the 1957-ITTC equation and its roughness allowance Cf. Theresult shows that the equation proposed by C is not applicable to characterize the impact offouling on hull resistance.