Measurement of charge distribution around a rising bubble in a 2‐D fluidized bed

On the electrostatic equilibrium of granular flow in pneumatic conveying systems

“…From all point charges in the cross section of the pneumatic conveying system, the total electrostatic field at the point (i, j) can be calculated as: (9) where l ranges from 1 ϳ m except i and k ranges from 1 ϳ n except j.…”

“…For free bubbling fluidized beds, Yao et al 5 found that the amplitude of the electrostatic charge voltage signals increases with superficial gas velocity but decreases with humidity. More recently, Chen et al 9 developed a technique to determine the charge distribution surrounding a single rising bubble in a two-dimensional fluidized bed. Their new technique was independent of net charge buildup in the bed, not influenced by charge transfer such as with collision probes, and allowed the reconstruction of the complete charge distribution around bubbles.…”

Experimental investigation of electrostatic effect on bubble behaviors in gas‐solid fluidized bed

“…Mehrani et al developed an on‐line Faraday cup fluidized bed system and concluded that friction between gas and wall had little influence on electrostatic charges, while elutriation of fines was the main cause of charge accumulation in the fluidized bed. A technique has been developed by Chen et al to measure the charge distribution around a single rising bubble in a two‐dimensional fluidized bed using a number of induction probes. Their results indicated that the wake of the bubble was more negatively charged than the emulsion phase, and a nearly zero charge density inside the bubble was found.…”

Non-intrusive measurement and hydrodynamics characterization of gas–solid fluidized beds: a review

“…They are immune to extra charge transfer and are independent of net charge accumulation such as with contacting probes. The output of an electrostatic induction sensor is in the form of an induced charge signal [40,41], current signal [26], or voltage signal [35,42], based on which the charge distribution and charge level in a gas-solid fluidized bed are obtained. In addition, the solids velocity and relative concentration can be characterized through electrostatic signal processing.…”