Clarification of the influences of superficial velocity <i>U</i>_<i>g</i> and particle diameter <i>d</i>_<i>p</i> on the gas–solid flow characterizations in a rolling circulating fluidized bed (RCFB) by electrical capacitance tomography (ECT) method

The influences of the superficial velocity and particle diameter on gas–solid flow characterizations in a rolling circulation fluidized bed (RCFB) are clarified by using electrical capacitance tomography method. Gas–solid include time-space averaged volume fraction ᾱz′, time transition cross-sectional average 〈α〉t, radial profile 〈α〉r/R. Two kinds particles selected case that is 0.22 mm set to 2.0, 3.0, 4.0 m/s 0.45 4.0, 5.0 m/s. After analyzing results, main conclusions able be summarized as follows: First, when compared with velocity, ᾱz′ visualized from distribution images much more influenced diameter. Second, fluctuations 〈α〉t 〈α〉r/R tend serious under conditions larger lower riser’s height, which quantitatively explained fast Fourier transform spatial standard deviation 〈σs〉 Consequently, strategy guarantee both stability uniformity within RCFB proposed.