一种高容积阻力比水下热滑翔机壳体外形设计

海洋温跃层的温差小,可利用的温差能的能量品质低,水下热滑翔机的热机效率较低,因此需要寻找最低阻力特性的热滑翔机壳体外形。利用水动力数值计算方法,分析了水下热滑翔机4种壳体外形的阻力成因和各自的优缺点,并采用2种不同的求解器对4种壳体外形阻力进行数值计算,不同求解器的计算结果最大偏差小于5%。提出了一个"容积阻力比"的无量纲系数,以此作为评判水下热滑翔机壳体外形综合性能的指标;将纺锤体外形与椭球体首尾外形的优点相结合,提出了水下热滑翔机的新型壳体外形。相比先前讨论的4种壳体外形,该外形具有最大的容积阻力比系数,表明该外形设计在水下热滑翔机的低阻特性与装载能力2种性能之间取得了较好的平衡和兼容。

Hull Form Design of Underwater Thermal Glider with High Ratio of Capacity to Drag

The thermocline of ocean has small differences in temperature that results in low quality of energy available for the underwater thermal glider, and therefore the efficiency of the thermal engine of the un- derwater thermal glider is not satisfactory. For this reason, it is necessary to design a kind of hull form with minimum drag performance. Based on numerical calculation of hydrodynamics, the hydrodynamic resis- tances of four common hull forms were analyzed, and their advantages and disadvantages were compared. Then two different hydrodynamic solvers were used to perform the numerical calculations. The results showed fair agreement with each other, while the largest deviation between them was less than 5 percent. Thus, a none-dimensional coefficient known as ＂capacity to drag ratio＂ was introduced, and the ratio was taken as the criterion to evaluate the overall performance of hull form. Furthermore, a new shape which combined spindle shape and shape with eclipse head and tail was proposed. The new designed shape has higher ratio of capacity to drag, in comparison with the other four common hull forms, and provides a good balance and compatibility in low-drag property and capacity performance.