Highly oscillatory flow regimes that can occur in gas-lift oil wells have been successfully treated using conventional linear control. However, these control systems rely on downhole pressure measurements which are unreliable or even unavailable in some cases. In this paper we propose a solution based on a high gain observer for the state of the process. The estimates are used to compute the do...

Oil wells with an oscillating production rate have a lower production compared to oil wells producing at a constant rate. This study looks at instability caused by the casing-heading phenomenon. Control is applied to achieve stable production rate. Two realistic gas lifted systems for oil and gas production are investigated, using the multiphase flow simulator OLGA2000. Different control struct...

NASA’s research into distributed electric propulsion (DEP) includes the design and development of the X-57 Maxwell aircraft. This aircraft has two distinct types of DEP: wingtip propellers and high-lift propellers. This paper focuses on the unique opportunities and challenges that the high-lift propellers—i.e., the small diameter propellers distributed upstream of the wing leading edge to augme...

Diesel and biodiesel spray combustion in a high temperature and high pressure environment was investigated in a constant volume combustion chamber. The effects of ambient gas temperature and ambient oxygen concentration on the combustion process were studied. The ambient temperatures varied from 800 K to 1200K, while the ambient oxygen concentrations varied from 21% to 9%. The results indicate ...

An Intelligent Supervision Scheme for the Industrial Production is presented in this work. Such scheme is tested for gas lift (GL) oil wells. The proposal is based on the possible production assessment, the process variables (specifically, the bottom-well pressures), and the operational scenarios detection for the process (in the case of study, as an oil producing well), with the objective of o...

— Gas-lifted wells often present unstable behaviors that cannot be described by hydrostatic laws. In this thesis, we aim at analyzing the well dynamics, especially when its production is irregular. We end up by designing control solutions. We begin with a brief description of the gas-lift activation technique. The negative impact of instabilities on oil production is underlined. Two main mechan...

The Object of this paper is to design and analyze a Hysteresis modulation based sliding mode control (HMSMC) for positive output elementary super lift Luo converter (POESLLC), which is the start-of-the-art DC-DC converter. The positive output elementary super lift Luo converter performs the voltage conversion from positive source voltage to positive load voltage. This paper proposes a HMSMC cap...

OBJECTIVE To determine if there is any observable difference in the midface of patients who have undergone a deep-plane face-lift vs a standard superficial musculoaponeurotic system (SMAS) plication face-lift. DESIGN Preoperative and postoperative photographs of 25 patients undergoing each type of face-lift were rated by 3 independent and blinded observers. A 7-point scale was used to grade i...

The MRA platform is one of the offshore platforms located in north Java Sea. has 4 production wells, namely MRA-2ST, MRA-4ST, MRA-5, and MRA-6 wells. wells are produced using an artificial lift form a gas lift. limited at Platform 3.1 MMSCFD makes not optimal because experiencing insufficient Optimization injection obtained by redistribution for each. results analysis this study indicate that o...