Welltest analysis of intermittent pumping wells based on finite element method

The intermittent pumping technique is often used in the low-permeability reservoir with poor deliverability. In this case, bottom-hole pressure fluctuates periodically and welltest theory in the situation of continuous pumping production is not suitable for intermittent pumping case, due to neglecting pressure buildup per cycle. So it is now necessary to study bottom hole pressure variation regularity of an intermittent pumping well and its welltest interpretation method. First, considering threshold pressure gradient and effects of wellbore storage and skin, mathematical models of intermittent pumping wells for non-Darcy flow at low velocity are established, and mathematical models are solved by using finite element method. Then corresponding type curves are drawn and effects of wellbore storage and skin, mobility ratios and threshold pressure gradients are analyzed.