Collocation Trefftz method applied to groundwater tidal effect analysis

Abstract

In coastal areas, tidal power causes periodic fluctuations of groundwater in coastal aquifers. In this paper, the response model of groundwater caused by tide is established by using the collocation Trefftz method (CTM) combined with the space-time coordinate system. Based on the governing equation of tidal response groundwater, the complete Trefftz basis of the equation is linearly superimposed, and the space-time coordinate system is combined to solve the variation of groundwater level with time and distance in the nearshore confined aquifer with tidal boundary. In this paper, the parameter sensitivity of numerical examples of CTM is analyzed by using analytical solution, and the parameter range of CTM to obtain highly accurate calculation results is discussed. In addition, this paper uses the CTM to analyze the tidal effect of groundwater, which has a strong practical significance for the application of this method to the study of coastal groundwater.