Study on the variation law of hydraulic jump values of pumping well in the loess aquifer

Abstract

Abstract This study aimed to investigate the influencing factors for the water jump and the research status of the solution. Using the in-situ pumping test, the analytic solution method, the curve-fitting method, and the method for determining the water-level difference of the main and auxiliary wells were put forward to calculate the characteristics of the water jump under the condition of constant flow. The water jump values obtained by different methods were compared. The duration change of the water jump value under three constant-flow pumping conditions was analyzed. Also, the relationship between the water jump value and the duration of the flow rate under three unstable flow conditions was examined. The results showed that, with reference to the analytical solution of the jump value, the value calculated by the difference method of primary and secondary water levels was about 17% and that calculated by the curve-fitting method was about 10% under the condition of constant-flow pumping. When the pumping amount increased to a certain value, the jump value was stable in a certain period of time. When the pumping volume increased to a certain value, a linear relationship was found between the pumping volume and the water jump value for a certain period of time under the condition of unsteady-flow pumping, but this relationship did not repeat completely. The results showed that it was difficult to calculate the magnitude of the water jump under the in-situ test strip. Further, the method for determining the water-level difference between the main and auxiliary wells could be used to approximate the water jump of the pumping well. It was confirmed that a linear relationship existed between the water jump value of the main well and the pumping amount under certain conditions during the pumping process. This linear relationship was affected by various factors and did not always exist.