Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Characteristics of the Starting Flow of a Rushton Turbine Mixer

러쉬톤 교반기의 초기 비정상 유동 특성

  • Published : 2001.11.01
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Abstract

The characteristics of starting flow of a six-blade Rushton turbine mixer were investigated by using a cinematic Particle Image Velocimetry technique. The flows were quantified by measurements of velocity fields with a 4 ms time interval for a blade rotational speed of 100 r.p.m, so that the turbine Reynolds number(ND$^2$/ ν) was fixed to 6,960. The radial shedding of the trailing vortices starts from passing four blades after the beginning of rotation. It clearly shows that the vortex pairing phenomena caused by the interactions between trailing cortices firm consequtive blades. The average convection velocity of the radial flow is found to be 28 % of the tip velocity. The starting flow seems to arrive at a steady state after 8 revolutions in this study, which corresponds nearly one circulation through the bulk flow trajectory with the average radial convection velocity.

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References

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