Unsteady Motion in Pipe Flow of Dense Gas-Solid Suspensions REU Supplement

点击翻译按钮获取中文摘要

Narrative: Unsteady stratified motions have been observed in dense gas-solid suspensions at moderate and low velocities, but means for prediction are lacking. This flow range is significant because it is energy efficient for processing and transport of solids and because it tends to minimize attrition of solids and erosion of equipment. With test loop systems of 2-inch and 5-inch pipe diameters capable of continuous recycling of solids, a minimum investment of solid material is needed for prolonged test runs. The large pipe especially makes possible detailed observation and measurements. A preliminary study showed that wave motion and phase interactions at a low velocity can be directly observed, and comparison to simple wave analysis can be made. At moderate velocities and large particle densities, measurement of wave motion in terms of a spectrum based on autocorrelation of probe current or local mass flow was feasible. The proposed research includes further work on basic formulation and transport properties, and definitive measurements over a range of unsteady horizontal pipe flow at first. Both auto and cross- correlations will be determined at various positions in the pipe over a range of flow conditions and particles. The aim is toward prediciton of flow conditions and scale-up of designs.