Active control of the production choke valve is the recommended solution to prevent casing-heading instability in gas-lifted oil wells. Focus of this work is to find a simple yet robust control structure for stabilization of the system. In order to find suitable control variables, a controllability analysis of the system with different candidate control variables and two alternative manipulated...

Based on the propagation rules of electromagnetic waves in metal conductors, this paper analyzes the characteristics of electric field and magnetic field of internal conductors. Then the complex power of electromagnetic wave is calculated. The impedance calculation formula of metal conductor is derived. Moreover, in order to identify and detect defects of metal casing, an alternating current im...

The costs associated with drilling and completing wells are a major factor in determining the economic feasibility of producing energy from geothermal resources. In EGS power plants, estimates place drilling costs as accounting for 42%-95% of total power plant costs (Tester et al., 1994) depending on the quality of the EGS reservoir. An earlier correlation first developed by Milora and Tester (...

The plastic deformation and interface micro annulus of oil-well cement during acid fracturing are key reasons for the failure wellbore seal sustained casing pressure. However, most existing research ignores influence cooling effect fracturing, owing to which, design conditions in theoretical analysis may be inconsistent with those actual wellbore, calculation results biased. In this study, a no...

Enhanced fracture stimulation processes are generally used in the petroleum industry to increase the recovery of hydrocarbon reserves. In the in the United States in particular, more efficient and cost-effective reservoir fracturing treatments are needed to enhance the recovery of oil and natural gas in those stripper wells that are characterized by low-permeability reservoirs. Proposed is a we...