Numerical Simulation of Dense Phase Pneumatic Conveying in Long-Distance Pipe

Computational Fluid Dynamics is now a new ramification of the numerical discretization method based on high-performance electronic computers, which focuses on fluid mechanics simulation. Fluid mechanics has two main braches that one is theoretical analysis and another is experimental research. Therefore, theoretical and experimental fluid mechanics were created as most important constituents in early days. Although the theoretical method could give the quantum results of the solving problem, it was still little used for its complicated solution procedure. Computational fluid mechanics has developed rapidly to cover the shortage of theoretical method. It has been involved each fluid field though its development history is short. Many numerical solution methods were formed according to different simulation purpose. Finite difference calculus and finite element method were mainly involved. In the application, Finite difference calculus was usually used in resolving fluid problem, while finite element method was exploited to research solid mechanics themes. Gas-solids two phase flow means solid particles are conveyed by compressed gas phase. The particles’ traces are irregular, which caused by the dispersion action and coupling force between gas and solids phase. The interaction process leads to the irregular motion of gas solid two phase flow and the flow characteristic parameter altering greatly. Nowadays, the recognization and analysis of gas solid two phase flow was not enough with limitation of test technique, which restricted the application development and system optimization of gas solid flow. So some fresh technique must be appeared to suit the application situation. Until now, the research technique in gas solid two phase flow focus on experiment cases because of the complexity of gas solid flow. Te gas solid two phase flow theory became more and more sophisticated with the development of particle dynamics and aerodynamics. Both had some deficiency. For example, in experimental research, calculation of some conveying parameters mostly depends on empirical equations based on experiments which leads to the limitation, and which are the same with its experimental condition commonly and generalized hardly. Theoretical studies are mostly short of accuracy because of lots of hypothesis in the process of deduction. Therefore, in this thesis, simulation study on the process of dense-phase gas-solid two phase flow was carried on based on experimental and theoretical investigations in order to cover the shortage of experimental and theoretical investigations.