Modeling and Analysis of Solids Friction Factor for Fluidized Dense Phase Pneumatic Conveying of Powders

Pressure drop in pneumatic conveying is due to frictional interaction among gas, particle, and pipe wall. Fictional forces due to solids can be calculated using a solids friction factor. Many correlations have been proposed for predicting solids friction factor in dilute phase pneumatic conveying. These correlations are calculated based on value of the parameters calculated for a long pipeline or value of the parameter at the inlet of the pipeline. Pneumatic conveying in long pipelines suggests that some of the flow parameters are not constant along the length of the pipeline. This article presents a modeling technique for predicting solid friction factor taking into account of the local value of flow parameter. In this method, the solids friction factor is presented in terms of coefficient and exponents. The values of coefficient and exponents are predicted for fluidized dense phase conveying using different types of conveying materials. Values of coefficient and exponents are found to be different for different types of conveying materials. Variations of different parameters are studied using the calculated optimum values of coefficient and exponents. Experimental data are also used to find the possible maximum conveying distance or pipe diameter by imposing certain limiting conditions of conveying.