Application of Gas Dynamics Principles to Pneumatic Conveying of Suspensions

摘要

The concepts of Generalised Steady One-Dimensional Flow are used to analyse the flow of gas-solids suspensions in pneumatic conveying pipes. The suspension flow is described in terms of equations of conservation of mass, momentum and energy, and auxiliary equations such as the ideal gas equation of state. The first-order linear differential equations, written in terms of 'Influence Coefficients' and 'Driving Potentials', are solved simultaneously. This approach enables identification and quantitative determination of factors influencing different flow variables. Parametric results are presented for different suspension flows. A dilute suspension, in particular, can be treated as an ideal gas with modified properties in which compressibility effects are heightened due to the presence of particles. The technique is validated against experimental data obtained from pneumatic conveying of soda ash and corvic vinyl in horizontal pipes. The agreement is fairly good, despite questionable accuracy of the assumed initial conditions. The method is also used to generate realistic pneumatic conveying characteristics (PCCs). It is possible to extend the analysis to pneumatic conveying in vertical pipes by adding the gravity term and perhaps to pipes with bends by including 'Impulse Function' in the list of variables investigated.