An Experimental Investigation on the Effect of Various Swirl Atomizer Orifice Geometries on the Air Core Diameter


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Liquid atomization is a process of changing the liquid into small droplets. There are many applications which are related to liquid atomization including fuel injection in combustion systems and also in agricultural sprays. In pressure swirl atomizer, the liquid is injected into the atomizer through tangential port and a swirling motion is formed inside the swirl chamber. In high strength of swirling motion, an air core will be visible inside the atomizer. The liquid is then discharged from the orifice to form a spray which breaks up the liquid into small droplets. The objective of this research is to investigate the effect of various orifice geometries on the air core diameter. The injection pressure was varied in the range of 2 to 8 bar and water was used as the working fluid. Experiment data shows that the air core diameter increases as the injection pressure increased, regardless the discharge orifice diameter and discharge orifice length. It also found that the air core diameter increases as the discharge orifice length decreases and the discharge orifice diameter increases.



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Edited by:

R. Varatharajoo, E. J. Abdullah, D. L. Majid, F. I. Romli, A. S. Mohd Rafie and K. A. Ahmad




M. S. F. M. Rashid et al., "An Experimental Investigation on the Effect of Various Swirl Atomizer Orifice Geometries on the Air Core Diameter", Applied Mechanics and Materials, Vol. 225, pp. 32-37, 2012

Online since:

November 2012




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