Numerical Simulation And Experimental Study Of Hydrodynamic Cavitation Based On Orifice Plate And Jet

Hydrodynamic cavitation is a new type of water treatment technology,Compared with other sewage treatment methods,there are certain advantages in energy efficiency.But the technology is still in the stage of basic research,Some key issues still need to be solved in the application of large-scale market.The main purpose of this paper is to explore the mechanism and effect of hydraulic cavitation enhancement effect by CFD software FLUENT,and to find the basic law of cavitation enhancement effect.Cavitation generator is the key part of water treatment.By comparing several kinds of hydraulic cavitation generators,the optimum parameters of the cavitation structure are obtained,and a new type of Venturi tube and orifice plate and its composite structure are designed.The main results of this paper are as follows:(1)By comparing with the experimental results,In FLUENT,The numerical simulation results of the combined cavitation plate with the Venturi tube combined with the k-? standard model and cavitation bubble dynamics model are in good agreement with the experimental results,the results show that the model is reasonable and the applicability of the algorithm.(2)When the outlet pressure is constant,inlet pressure below 0.4MPa,With the increase of pressure,the cavitation effect increases,Best results in 0.4MPa.When the inlet pressure is greater than 0.4MPa,increasing inlet pressure will reduce cavitation effect.(3)Temperature is also an important factor affecting cavitation effect,by comparison between simulation and experiment,Obtained at 20? ~40?,With the increase of temperature,the cavitation effect increases gradually,the effect of cavitationis better in 40?.When the temperature is higher than 40?,the cavitation effect decreases with the increase of temperature.(4)Simulation results show,the viscosity of the liquid can inhibit the cavitation effect.With the increase of liquid viscosity,the cavitation effect becomes weaker.With the increase of surface tension,the vapor holdup is almost unchanged,which indicates that the surface tension has little influence on the cavitation effect and can be ignored.The simulation of initial gas content,The cavitation intensity increases with the increase of the initial gas content in the liquid to the thousandth(this paper is 0.005).The cavitation intensity will decrease with the increase of initial gas content.(5)The structure of different orifice plates has an important influence on the cavitation effect of the composite cavitation.A better composite cavitation effect calculated by the simulation aperture of 22 hole ring shaped arrangement of the orifice pipe combined with Venturi,The results showed that the degradation rate of phenol was21.05%,which was higher than that of Venturi tube.Consistent with the experimental results.