Cyclone pressure drop

Cyclone Pressure Drop. Typical cyclone pressure drops range from 250 to 2000 Pa. Most data are reported for clean air flowing through the cyclone and these data are conservative for design purposes. Many investigators have unsuccessfully attempted to relate pressure drops to inlet and oudet dimension ratios. Manufacturers caUbration curves or experimental measurements on cyclones of similar dimension should be used where possible. If a rehable experimental measurement is available, however, the pressure drop at other conditions can be estimated by first evaluating the constant i in equation 17. 

Some empirical equations to predict cyclone pressure drop have been proposed (165,166). One (166) rehably predicts pressure drop under clean air flow for a cyclone having the API model dimensions. Somewhat surprisingly, pressure drop decreases with increasing dust loading. One reasonable explanation for this phenomenon is that dust particles approaching the cyclone wall break up the boundary layer film (much like spoiler knobs on an airplane wing) and reduce drag forces. 

K Empirical proportionality constant for cyclone pressure drop or friction loss Dimensionless Dimensionless ... 

Calculate the cyclone pressure drop and, if required, select a suitable blower. 

Insufficient cyclone pressure drop this may occur during start-up or turndown operations... 

The influence of temperature and inlet velocity on cyclone pressure drop ... 

In this study, four empirical models in the literature have been chosen to predict the pressure drop over a cyclone, namely Shepherd and Lapple [11], Casal and Martinez [3], Dirgo [5], and Coker [4], In these four models, the total pressure drop in cyclone is either assumed equal to the static pressure drop or as a function of cyclone dimension and pressure drop coefficient. Generally cyclone pressure drop is proportional to the velocity head and can be written in the form of... 

Measurement of the cyclone pressure drop was carried out for inlet velocity ranging from 4.62 to 14.16 m/s by Bohnet [2], and from 5.1 to 25 m/s by Griffiths and Boysan [8], The numerical calculation was made with a fine numerical... 

Measurement of the cyclone pressure drop of different operating temperature was carried out for temperature ranging from 293 to 1123 K by Bohnet [2]. The comparison between the Bohnet experiment, empirical model and CFD prediction is shown in Figs. 7 and 8. Fig. 9 shows the three-dimension map of static pressure for operating temperature of 950 K. 

The cyclone pressure drop can be rewritten as a function of inlet velocity head. The model used for the prediction of pressure drop depends on the cyclone operating condition. Both Shepherd and Lapple, and Dirgo models show a good prediction on cyclone pressure drop under different operational inlet velocity. However, Dirgo s model is unable to predict accurately the pressure drop under different operating temperature. For the various temperature conditions, Shepherd and Lapple s pressure drop model prediction is the best. We therefore, conclude that the Shepherd and Lapple model should be used for estimation of pressure drop in cyclone design. 

Cyclone pressure drop is essentially a consequence of the vortex energy, the solid loading and the gas-wall friction. The main contribution is the suspension vortex energy. Generally, the pressure drop through a cyclone is proportional to the velocity head and approximated by [111] ... 

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