Local gas holdup, mean liquid velocity and turbulence in an aerated stirred tank using hot-film anemometry

Flow Generated by an Aerated Rushton Impeller: Two‐phase PIV Experiments and Numerical Simulations

“…When gas was introduced from a sparger below the impeller blade, the symmetrical vortices were destroyed. This however disagrees with the measurements of Lu and Ju (1987), who still observed the vortices. When the flow fields for 10°, 20°and 30°are compared, the influence of the position of the impeller blade on the flow field is less pronounced than in the unaerated case.…”

“…When gas is present, the jet is no longer directed downwards, but as an effect of the gas pulled upwards. This is in correspondence with observations of Lu and Ju (1987). In the centre of the tank (the bottom right part of the measurement plane) gas bubbles are rising and entrained in the impeller stream.…”

“…Measurement C/T Flow Measured technique type quantity Costes and Couderc (1988) LDA 1/2 L u L Derksen et al (1998) LDA 1/3 L u L Lu and Ju (1987) CTA 1/2 G-L u L Morud and Hjertager (1996) LDA 1/2 G-L u G Roušar and Van den Akker (1994) LDA 1/3 G-L u L Rutherford et al (1996) LDA 1/3 L u L Sharp et al (1998) PIV 1/2 L u L Stoots and Calabrese (1995) LDA 1/2 L u L Wu and Patterson (1989) LDA 1/3 L u L Yianneskis et al (1987) LDA 1/2 L u L A two-camera PIV technique was used to obtain angle resolved velocity and turbulence data of the flow in a lab-scale stirred tank, equipped with a Rushton turbine. Two cases were investigated: a single-phase flow and a gas-liquid flow.…”

Large eddy simulation of the gas–liquid flow in a stirred tank

“…The geometry of the stirred tank simulated in this work is depicted in Figure 1, consisting of a cylindrical tank with a standard six‐blade Rushton turbine and four baffles on the tank wall, as the same as that tested by Lu and Ju 33. The tank was filled with water at room temperature.…”

Quantitative measurement of gas hold-up distribution in a stirred chemical reactor using X-ray cone-beam computed tomography

“…The range of methods extends from liquid level measurement, hot wire anemometry [2], suction probes [3,4], electrical probe measurements [5][6][7], optical holography [8], particle image velocimetry [9], ultrasound techniques [10], X-ray radiography [11][12][13], electrical impedance tomography [14,15], positron emission tomography [16], and transmission computed tomography using X-rays or gamma radiation. With no doubt methods based on ionising radiation are the most promising since they are non-invasive, they can achieve a high spatial resolution, and they give linear measurements regardless of the structure complexity inside the vessel.…”