Theoretical Analysis on Mobilization of Aquifer Particles Induced by Groundwater Source Heat Pump Pumping

Abstract:

The mobilization theory of aquifer particles induced by groundwater heat pump(GWSHP) pumping is theoretically studied in this work, which includes analysis of forces working on the particles and the releasing mechanism. A case study, which represents a kind of typical aquifer in Tianjin, is carried out. Such parameters as water discharge, aquifer thickness and borehole diameter are analyzed based on the calculated values of critical hydraulic gradient and the critical seepage velocity. The present studies indicate that the particle mobilization is directly influenced by the aquifer thickness and the borehole diameter under the same water discharge. It is aimed to provide some theoretical basis to solve the problems of borehole collapse and particle regrouping in the GWSHP’s long-term operation.

Key words:groundwater source heat pump; particle mobilization; aquifer thickness; borehole diameter