Experimental Study of the Hydraulic Performances of Two Three-Bladed Inducers in Water, Water With Dissolved CO2, and Jet Fuel

Abstract

Inducers in centrifugal pumps are generally placed upstream to increase the pressure before the impeller and prevent cavitation occurrence. Their general goal is to obtain a positive impact on the performances of a pump in a two-phase regime. Cavitation phenomenon has been the subject of many studies; however, the influence of the presence of dissolved gas in the liquid pumped under particular operating conditions remains not sufficiently explored. To the best of our knowledge, aviation jet fuel cavitation is moderately documented. In the present work, we conducted an experimental study on two three-bladed axial inducers at partial flow rates only in cavitating and noncavitating regimes. The experimental work used aviation jet fuel, water, and water with dissolved content of CO2 at constant temperature in two closed loops with transparent test sections. In one tank, a specific device is placed to inject a controlled quantity of CO2 and to dissolve it in water. We achieved a comparison of the flow dynamics through the use of a high-speed camera with a sampling rate of 1000 Hz. The results show inducers' water–CO2 cavitation performances to be in good agreement with aviation jet fuel cavitation results.