Numerical Simulation Of Two-phase Flow In Gas-solid Fluidized Process

For a long time,due to the influence of natural and human factors,the soil erosion in the Loess Plateau of China has been serious,and it has also caused the problem of reservoir siltation.The safe operation of the reservoir is threatened and its benefit is limited.There are still a lot of waste Silts in the reservoir which are damaged by siltation.Therefore,it is necessary to use the technology of storage capacity maintenance to revive dead storage capacity in the area of sandy river.It is a very effective measure to blow up air to the reservoir area through the bottom outlet of desilting so that the silted sediment can be discharged smoothly from the bottom outlet of desilting.In this paper,the numerical simulation of the gas-solid fluidization process at the bottom outlet of the reservoir is carried out by using the self-made program,and the results obtained have certain reference value for the practical application of the project.The specific research content of this paper is as follows:1.Firstly,the research results of two-phase flow at home and abroad are summarized,and the commonly used two-phase flow models are compared to determine the two-phase flow model selected in this paper.Secondly,the governing equations of the two fluid model are introduced,and the required constitutive equations are given according to the closure principle of the equations.Then,in terms of numerical simulation,based on Patankar’s theoretical results on fluid flow,using the improved SIMPLE algorithm,a two-phase flow program is compiled to simulate the gas-solid fluidized process,and compared with the previous test results,which proves the correctness of this program.2.The numerical simulation of the gas-solid fluidized process under four working conditions is carried out,and the influencing factors of the jet(or bubble)are analyzed in detail.It is concluded that when the jet velocity is larger,the gas velocity of the distribution plate is the minimum fluidized gas velocity,and the jet area nozzle diameter is larger,the bubble is larger.According to the distance between the two jets,the two jets are divided into direct acting jet,indirect acting jet and non acting jet.