An analysis has been completed for a comprehensive set of vertical, dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow. The data were collected in the established flow region for eight different materials conveyed in 0.05-, 0.10-, 0.20-m internal diameter, 20-m tall steel risers. Particle velocities derived from the pressure drop data were used to develop an equation of motion that includes terms for pipe diameter, terminal velocity, coefficient of restitution, and particle shape. The best data fit was achieved using the actual gas density and the actual gas velocity adjusted for voidage. Adjusting the terminal velocity for voidage, an approach recommended by many investigators, did not improve the fit for reasons identified by the present research.

Using the equation of motion, particle velocities were predicted and used to calculate total pressure drops that are within ±15% of the measured values. The calculated values also produce the characteristic trough-shaped total pressure drop curves allowing the minimum pressure drop gas velocity to be determined without recourse to a separate correlation. A comparison with other studies using shorter risers indicates that data from these studies likely include acceleration effects. A separate study will investigate this observation further.

已经完成了对 Flatow 调查中的一组综合垂直、稀相气力输送压降数据的分析。数据是在确定的流动区域收集的，用于在 0.05 米、0.10 米、0.20 米内径、20 米高钢立管中输送的八种不同材料。从压降数据导出的粒子速度被用来开发一个运动方程，其中包括管道直径、终端速度、恢复系数和粒子形状的项。最佳数据拟合是使用实际气体密度和针对空隙率调整的实际气体速度来实现的。调整空隙率的终端速度，这是许多研究人员推荐的方法，但由于本研究确定的原因并没有改善拟合。

使用运动方程，粒子速度被预测并用于计算总压降在测量值的 ±15% 内。计算值还产生特征槽形总压降曲线，允许确定最小压降气体速度，而无需求助于单独的相关性。与使用较短立管的其他研究进行比较表明，这些研究的数据可能包括加速效应。一项单独的研究将进一步调查这一观察结果。