Experimental Study of the Effect of Drag Reduction Agents on the Performance of Jet Pumps

Abstract

The overall efficiency of the jet pump is low compared with most of the other types of pumps. The majority of previous investigations concentrated on the effect of its geometric ratios on its performance. To the best of the authors’ knowledge, there are no previous investigations on the effect of adding drag reduction agents to the fluid passing on its performance, which is the objective of the present investigation. The mixing process in this case is that of two streams: the primary stream is water (Newtonian fluid), whereas the secondary stream is a solution of certain polymer (considered to be non-Newtonian). Tests are carried out to study the effect of different concentrations of additives (carboxy methyl cellulose (CMC)) on the performance of the jet pump. The experimental results include characteristic curves for different area ratios, with different concentrations of CMC, as well as the wall static pressure distributions along the mixing chamber, diffuser, and outlet pipe. The results show that the concentration have a pronounced effect on the overall efficiency. The efficiency increases with the increase in concentration, up to a certain value, then decreases at higher value of concentration. Further, the maximum overall efficiency increases with the decrease in values of area ratio ( R).