Solid State Science and Technology, Vol. 12, No. 1 (2004) 166-176



Andrew R.H Rigit1, John S. Shrimpton


1Faculty of Engineering, University of Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia.

Department of Mechanical Engineering, Imperial College London, Exhibition Road, London

SW7 2BX, England, UK.



This paper describes the characteristics of charged sprays of insulating liquids generated by charge injection electrostatic atomizers, assessed for a smaller range of orifice diameter and a more viscous liquid than previously investigated. The jet break-up dynamics are qualitatively studied with a high-speed video camera, and the general spray characteristics are quantitatively described in terms of droplet velocity and diameter pdfs with a phase Doppler anemometry (PDA). A  purpose-built transmitter and receiver, and a purpose-built signal- processing counter are used as the main PDA component. Spray charge and mass flow rate as a function of spray radius is also studied using a purpose-built collecting system, and the results suggest that highly charged droplets exist outside the spray cone.



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