Effects of liquid viscosity and injection pressure on the drop size distribution of the liquid spray from swirl atomizers were studied experimentally. Glycerine-Water mixture was used as a test fluid for the experiments. The drop size distributions of the liquid spray were measured with Malvern Particle Sizer. Deviation, $\sigma$, was introduced to represent the degree of the uniformity. Experimental results show that the spray becomes coarser and less uniform with the high viscosity liquid and with the low injection pressure due to difficulty in atomization. It was also confirmed that the SMD value increases with the high viscosity of the liquid and with the low injection pressure.
