EFFECT OF CYCLONE INLET VELOCITY AND VORTEX FINDER HEIGHT ON COARSE WHEAT BRAN DUST SEPARATION

Document Type : Original Article

Author

Associate Prof. of Agric. Eng. Dep., Fac. of Agric., Suez Canal Univ., 41522 Ismailia, Egypt.

Abstract

Experimental study was performed for evaluating a vast number of equations derived from reviews to determine the performance of cyclone for overall collection efficiency, cut size diameter and pressure drop of cyclone. These equations were used based on the geometrical design of cyclones for operation at the ambient temperatures under different vortex finder heights (0.0, 0.05, 0.10, 0.15 and 0.20 m) and inlet velocities (9.3, 11.5, 18.5, 25.4 and 28.3 m/s). The cut size diameter of coarse wheat bran as inlet dust was estimated using direct empirical method and by Stock's number based on Euler's number. Both methods were also used to predict the overall collection efficiency. Experimental data were compared with the predictions of Lapple's theory and Iozia & Leith's logistic method. The results showed that only the pressures drop based on Cocker model in the range of 9.3 to 18.5 m/s inlet velocity proved accurate predictions. The operation at inlet velocity of 18.5 m/s was the best operational condition due to high collection efficiency of 96.4, 98.9, 98.5, 98.3 and 98.7%; and low pressure drop of 1173, 1324, 1249, 1137 and 1419 Pa at vortex finder height of 0.0, 0.05, 0.10, 0.15 and 0.20 m respectively, across the cyclone.

Keywords

References

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Misr Journal of Agricultural Engineering
Volume 31, Issue 3
July 2014
Pages 1001-1024

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