Velocity and mass flow rate profiles of dry powders in a gravity drop conveyor using an electrodynamic tomography system

Abstract

This paper describes measurements made on a gravity drop conveyor using two arrays of axially spaced electrodynamic sensors to measure axial velocities close to the wall of the conveyor and velocity profiles both of flowing sand and of plastic beads. The level of correlation obtained using pixels is investigated. The velocity profile is combined with a tomographic concentration profile to estimate the mass flow profile, which is summed over the measurement cross section to estimate the mass flow rate. A calibration of the tomographically determined mass flow rate versus the actual mass flow rate is presented.

Process tomography and estimation of velocity fields

“…Different modifications of EIT-based cross-correlation method have also been used for estimation of angular velocities (Etuke & Bonnecaze, 1998) and radial flows (Bolton, Hooper, Mann, & Stitt, 2004). Another electrically based cross-correlation flowmeter uses electrodynamic tomography to estimate the flow of electrically charged particles (Green et al, 1997).…”

New Type of Medium – Gases with High Concentration of Nanoparticles

“…Кроме того, лазеру необходимо просвечивать достаточно большую толщину потока, соответственно, помимо геометрических ограничений на поток, это существенно усложняет расчет скоростей из-за многократных рассеяний. Извест-ны также работы, в которых использовалась электродинамическая томография [3] для осевых скоростных измерений вблизи стены конвейера с шариками, движущимися под действием силы тяжести. Более новые исследования порошковых потоков проведены с использованием рентгеновских лучей [4], допплеровской лазерной анемометрии [5] и магнитного резонанса [6], но каждый из этих методов имеет ограничения в применении.…”

Dual Modality Tomography System Using Optical and Electrodynamic Sensors for Tomographic Imaging Solid Flow

“…problem determines the theoretical output of each electrodynamic sensor when the sensing area is considered two-dimensional and contains a uniformly distributed charged of σ coulombs per square meter [12]. To solve the forward problem, the theoretical output of each sensor due to placing a certain surface charge σ at all the possible locations in the pipe cross section has to be calculated.…”