A Design for Ocean Thermocline Simulation Pool Based on the Similarity Theory

In order to simulate the thermocline characteristics of ocean environment and investigate the hydrodynamic performance of an underwater thermal glider navigating within，various characteristics of the ocean thermocline simulation pool are analyzed in this paper，based on the similarity theory. The pool is first designed to simulate the underwater thermocline layer with a depth no less than 10 meters and a temperature gradient of 0.2 Celsius degrees per meter. The technical parameters of the pool include the scaling factor，principal dimensions，temperature field and dynamical similarity coefficient. Next，the resistances of the glider model tested in the pool and that of the actual glider in the ocean are obtained using a numerical simulation approach and ITTC’s experiential formula of drag，respectively. Comparison between the results shows a difference less than 5 percent. Meanwhile，the temperature gradient of the pool is measured with a linear series of temperature sensors. The result also indicates a difference less than 3.5 percent compared with real data，which again validates the feasibility and reliability of the pool. It is found out that the temperature gradient ratio of the simulation pool to the ocean thermocline layer should be determined by the square of the scaling factor. Moreover，the adverse effects such as the blocking effect，shallow water effect and side wall effect could be well restrained by choosing an appropriate dimension of the pool.