<p> Energy loss was measured across a 3.0 inch hydrocyclone operating with and without an air core. </p> <p> The separational efficiency, as indicated by the (Dp)50 diameter, was measured as a function of feed concentration, feed flow rate and volume split. </p> <p> This (Dp)50 "cut size" was obtained from mass balances on the total solids and particle size distributions for the feed, overflow and underflow. </p> / Thesis / Master of Engineering (MEngr)