Method of evaluating the radius of influence of a circulating well based on hydraulic head difference

The radius of influence of a vertical circulation well was studied, taking the difference between the hydraulic head caused by the operation of the vertical circulation well and the initial state of the hydraulic head as the index. Based on the influence of well operation, the aquifer properties and technical parameters of the vertical circulation well on hydraulic head difference, an evaluation method for determining the radius of influence of the well was constructed. The software COMSOL Multiphysics was used to simulate the variation in hydraulic head and the flow field under different working conditions. The results show that increasing the operating time and flow rate, with an increased horizontal permeability, could lead to an increase of the influence radius, while an increase in the vertical permeability could lead to a decrease in the influence radius. Running time, horizontal permeability, vertical permeability, the distance between the lower screen section and the waterproof bottom plate, and the distance between the upper and lower screen sections, all have a great influence on the flow field. Thus, a calculation formula for quantitatively estimating the radius of influence of vertical circulation wells was obtained.