# Study on the Influence of Different Factors on Pneumatic Conveying in Horizontal Pipe
## 4 Simulation Results and Analysis
### Simulation Results and Analysis of Different Conveying Wind Speeds  
In order to study the influence of conveying wind speed on the conveying characteristics of particles, the conveying wind speed of other working conditions is set to 18 m/s, 26 m/s, and 30 m/s based on the benchmark working conditions, and the control variable method is used for simulation analysis. The simulation results are as follows. Figure 6a is the fluid dynamic pressure cloud diagram under different conveying wind speeds in the sampling section. It can be seen from (a) that, with the increase of conveying wind speed, the maximum dynamic pressure in the pipe increases from 300 Pa to 758 Pa, and the minimum from 29 Pa to 274 Pa, showing an overall increasing trend. Figure 6b shows the cloud diagram of particle mass concentration changes under different conveying wind speeds in the sampling section. It can be seen from (b) that, with the increase of conveying wind speed, the particle mass concentration in the pipe presents a decreasing trend, and the  
Figure 4: Simulation model parameters. Figure 5: Horizontal cross-sectional partition cloud diagram. maximum dynamic pressure and minimum mass concentration appear in the high-speed zone, while the minimum dynamic pressure and maximum mass concentration appear in the low-speed zone. When the conveying wind speed increases, the dynamic pressure increases and the particle mass concentration decreases. The analysis shows that, when the dynamic pressure increases, the kinetic energy of the particles increases, and the particles will be transported out faster in the pipeline. Meanwhile, the number of particles in the pipeline of the same length decreases, so the particle mass concentration decreases. At this time, the porosity of particles increases, which means that the interval between particles increases, and the probability of particle collision decreases. In actual transportation, collision will lead to breakage, and the breakage of particles reduced by collision will also be reduced. That is, the number of complete particles transported will increase, and the transportation efficiency will increase, which is conducive to the economy of transportation. Figure 7 shows the relationship between the average velocity of particles in the 0.5 m pipe length in the three zones with time under different conveying wind speeds. It can be seen from Figure 7 that the final stable velocity of particle groups in the three zones differs significantly with the change of conveying wind speed. The larger the conveying wind speed, the sooner the particles arrive at the sampling section, and the smaller the conveying wind speed, the later the time for particles to reach dynamic equilibrium in the sampling section, which is in line with the actual conditions. Figure 6: Distribution cloud diagram of fluid dynamic pressure and solid mass concentration under different conveying wind speeds. (**a**) Fluid dynamic pressure cloud diagram, Pa; (**b**) particle mass concentration cloud diagram, kg/m\({}^{3}\). Figure 7: Variation of average particle velocity with time under different conveying wind speeds. Figure 8a shows the average value of the final stable velocity of the particles in the three zones with the change of the conveying wind speed. From (a), we see that with the increase of conveying wind speed, the average velocity of the particle group after stabilization increases approximately linearly, and the value of the average velocity changes greatly. The trend of change is consistent in the three zones. Figure 8b shows the pressure drop of fluid along the pipe under different conveying wind speeds in the sampling section 7.5 m to 8 m away from the inlet. As can be seen from (b), the pressure drop gradually increases with the increase of conveying wind speed, but when the wind speed increases from 18 m/s to 22 m/s, the pressure drop increase rate is small. The pressure drop in gas-solid two-phase flow refers to the size of the driving force being consumed.