72 posts
Re: seperation efficiency of cyclones
thanks too much: thats i was needed and i have to quetions 1)is this calculations design same like ather bottom cyclones and what the differences if there? 2)what the relation equation for dip pipe design and what the difference between hot stream and cold stream(top cyclones and bottom cyclones)
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138 posts
Re: seperation efficiency of cyclones
elwathig,
The formulas take the temperature somehow into account since the cut diameter is detemined by the velocities and therefore by the density. In addition, the viscosity of the gas comes into play since the migration of the particles is slowed down by viscosity.
Concerning the effect of the dip tube, its length is taken into account in the Ioza and Leith fomula (or other formulas). In this formula, it is the (effective) height of the cyclone minus the height of the dip tube that matters. This suggests that the migration of the particles is not effective near the dip tube and occurs only below. Maybe this is due to urbulence? However, without the dip tube, the flow may well take a shorter path and not spiral down the whole height of the cyclone.
This is all about the "effective heigth" of the cyclone where the particle actually migrate outwardly if they are not too fine. Alexander in ref [1] determined a correlation for this "effective height" in a simple geometry without dip tube.
You may find much more in papers like these: http://caaqes.tamu.edu/Publications/Publications/PU00001.pdf
http://xa.yimg.com/kq/groups/3004572/1678732279/name/Rapid+Performance+Evaluation+and+Optimal+Sizing+of+Dry+Cyclone+Separators.PDF
[1] R. Mck. Alexander, Proc.Austr.Inst.Min.Met. 152 ,202,(1949)
31 posts
25 posts
Re: seperation efficiency of cyclones
Dear Sir,
Can any one suggest me the proper function of diptubes in cyclone?
What will be the separation efficiency and on pressure drop across the cyclone
:-if the height and dia is more of diptube
:-if the height and dia is less of dip tubes