Effect of the Gravel Zone Thickness Created in the Deep Well Test Simulation on the Operating Characteristics of the Pump and Head Loss

This study was conducted in a deep well simulator used for typical irrigation studies. In this work, the changes in the pump flow rate, drawdown, noise level, and pump pressures were analyzed for three different gravel zone thicknesses used in the well. From the study, it was found that a high gravel zone thickness increased the well’s drawdown levels during pumping. For drawdown values of 40, 45, 50 and 55 m3 h–1, an increase in the gravel thickness by 10 cm increased these values by 2.92, 2.41, 2.38 and 2.37 times, respectively. When the gravel thickness was doubled (from 5 cm to 10 cm), the hydraulic conductivity decreased by about half and head loss doubled. As a result, gravel thickness directly affected the drawdown rate of the pump. It was shown that different drawdown values resulting due to different gravel thicknesses should be taken into consideration when placing the pump in a deep well.