So far, there have been published on cyclones particularly concerning with the flow pattren of gas and liquid, the pressure drop or energy loss of fluid in the cyclone, the total efficiency of collection of dust and with the fractional collection efficiency for the steady dust-laden gas flow.
Authors made the fundamental experiments of the cyclones for steady dust-laden gas flow and pulsating dust-laden gas flow in ordinary atmosperic conditions. Four types of cyclones are similar and are made by transparent plastic material. As a test dust, fly ash was used. The cumulative distribution of dust by weight was
R(
x)=100exp[-ln2(
x/
xR50)
1.97].
This dust was fed into cyclones with constant concentration of C (g/m
3).
The equation of the fractional collection efficiency which was confirmed by the experiments is generally written as follows;
η
x=1-exp[-ln2(
x/
xC50)
m].
wherre
m is the exponent which means the sharpness of the classification of separated particles.
The pulsating air flow was produced by rotating a disc setting in front of the cyclone inlet pipe. The rotational speed
N of this disc was between 200-500 (ppm).
The experiment showed that the cut-sizes of the cyclones have different characteristics for the steady and pulsating dust-laden gas flow, that is while the cut-sizes are increasing with decreasing the inlet velocity
U0 in case of steady gas flow, for the pulsating dust-laden gas flow, the cut-sizes arechanging over 0.5-3.5 (μm) range with increasing the mean inlet velocity
U0.
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