A Preliminary Laboratory Investigation of a Hydraulic Ram Pump

The nexus of food, energy, and water is one of the most complex issues that face society. By 2050 the Earth’s population is expected to exceed 9 billion and most of the population increase will occur in developing countries. In addition, water scarcity will be particularly pronounced in the Middle East/North Africa and the South Asia regions and is likely to worsen as a result of the climate change. Within this framework, we revised the use of the hydraulic ram as a possible solution to supply water in remote areas. Experimental results of a preliminary investigation carried on a hydraulic ram pump assembled at the Laboratory of Environmental and Maritime Hydraulics of the Department of Civil Engineering, University of Salerno, Italy showed that geometric parameters as well as material properties affect its operating efficiency. The effect of the impulse valve on the pressure temporal trend is assessed by processing video recordings taken with high-speed digital cameras with a sampling rate of 1 KHz. Most of its effect is produced when the percentage of valve opening is in the range 0–20%, where correspondingly the valve coefficient Kv varies of about 80%. Unsteady pressure profiles were detected by means of pressure transducers with an acquisition of up to 1 kHz. The system of acquisition revealed the existence of a family of transient shock waves which intensity depends on the system’s features.