新型三维内波及分层流水槽系统

A New Type of 3D Internal Wave and Stratified Flow Tank

本文提供了作者研制的三维内波及分层流水槽系统的背景技术资料。经源致三维内波的实验证实 ,利用该水槽系统中的双缸制取分层水系统可快速制取所需的分层水 ,不必利用分子扩散而 1次得到预先设置的密度剖面。同时 ,还介绍了利用该水槽系统进行的 1个典型的源致内波的内波增阻实验。从所获得的增阻实验结果得知 ,对于一给定的分层、拖曳速度和水下回转体 ,存在唯一 1个内Froude数使得强迫源受到最大的内波增阻。大量的实验证实 :该水槽系统是研究三维自由和强迫内波的 1个基本实验系统。

The technical background materials on a new type of 3D internal wave and stratified flow tank are provided in this paper. From the experiments of 3D internal waves, it is shown that the two-tank filling system can produce a priori designed density profile without using the layer by layer molecule diffusion and mixing method. For a simple density profile of two-layer flow, the filling time is 2.5～3h, and for complex density profiles, the time required is 3.5～4h. The measurements of the density profile and internal waves can be conducted by using the internal wave meter, and a two-component force meter can be used to measure the drag and the lift etc. A typical experiment of drag increment due to forced internal waves carried out by this tank system is described. The experimental results of drag increment show that for given stratification, towed-speed and underwater spheroid, there exists only one internal Froude number Frd at which the spheroid stands a maximum drag increment. A number of experiments also show that this tank system is a basic facility for studying the behaviour of 3D free and forced nonlinear internal waves.