| Based on the research of flotation column technology, the research progress of microbubble generator and multiphase theory were systematically introduced, the features of some flotation columns and microbubble generators which were widely applied in the world were illustrated.Based on hydrodynamics theory, the principle of dissolved air and jet into bubble and the effect of microbubble and particle. The work mechanism of mixed flow microbubble was studied, and the basic performance equation and inflatable performance equations were constructed. The internal flow field of generator was analyzed, and the method of calculating microbubble diameter and measuring distribution was put forward.The mircrobubble generators with different radius of jet sphere groove, throat pipe, various diffusion tube taper angle and outlet pressure were simulated by using CFD software FLUENT. The variations of flow filed what is caused by these parameters was analyzed based on velocity, kinetic energy, gas phase distribution, and the influence on microbubble generator performance.Parameterized modeling of GAMBIT was studied and the software was developed. The CFD software FLUENT was secondarily developed for mixed flow microbubble generator, what can improve the usage efficiency of FLUENT.Finally, the pure water forming bubble was experimented by using microbubble generator with different sphere groove radius; also the influence of inlet velocity and flotation column liquid level on generator performance was studied in the experiments. The selection of this thesis comes from the national natural science funds. The research result has some meanings in development of microbubble generator. |
