**4.3.3 Numerical calculation circuitry**

The numerical calculation circuitry is shown as below.

Numerical Simulation of Dense Phase Pneumatic Conveying in Long-Distance Pipe 389

Fig.7 shows dynamic pressure distribution along the pipe. From the diagram, we can know that the dynamic pressure decreased gradually in the upper of the pipe, while at the bottom of pipe the dynamic pressure increased on the contrary. The reason for the phenomenon is

Solid concentration can reflect the solid motion style directly in process of pneumatic conveying. But in the experiment research, it's hard to measure this parameter accurately. In this study, we use numerical simulation method to gain the solid concentration in pipeline,

Fig. 7. Distribution diagram of dynamic pressure.

the increasing of particle concentration at the bottom of pipe.

**4.4.2 Solid concentration distribution along the pipe** 

Fig. 8. Graph of concentration distribution.

as shown in Fig.8.
