The Study of Low-velocity Non-Darcy Flow for Low-permeability Media in North China Plain

Abstract

Vertical leakage across low-permeability strata and underflow from adjacent aquifers (interaquifer flows) can be important sources of recharge for groundwater aquifer. However, in low-permeability porous media, due to small-size pores in porous media and throat radius of a few micrometers, molecular force on the solid-liquid interface increases significantly, which leads to the low-velocity non-Darcy flow. Conventional groundwater modeling methods assume that groundwater flow is described by Darcian principles which are inadequate when the flow is low-velocity non-Darcy flow. In this study, experiments are performed to explore the mathematical relation between flow rate and hydraulic gradient of low-permeability media in North China Plain of China. Mathematical equation has been obtained by curve fitting method based on experiment data.