Results 231 to 240 of about 10,717 (265)
Some of the next articles are maybe not open access.
Modeling Coiled-Tubing Velocity Strings for Gas Wells
SPE Production & Facilities, 1998Summary Because of its ability to prolong well life, its relatively low expense, and the relative ease with which it is installed, coiled tubing has become a preferred remedial method of tubular completion for gas wells. Of course, the difficulty in procuring wireline-test data is a drawback to verifying the accuracy of the assumptions ...
John Martinez, Alec Martinez
openaire +1 more source
Decentralized Networked Control for Vehicle-String Velocity and Spacing
IFAC Proceedings Volumes, 2014Abstract Decentralized overlapping feedback control laws are designed for a vehicle-string bias system which controlled over networks in this paper. The dynamic model of vehicle-string bias system is treated as an interconnected system with overlapping states.
Distance Bias System +3 more
openaire +1 more source
COSMIC STRINGS AND ROTATION VELOCITY OF SPIRAL GALAXIES
Modern Physics Letters A, 1986Accretion of collisionless particles onto cosmic strings leads to the formation of galactic halos. The halo density is determined uniquely by the string-line density µ as ρ(r)=µr−2 where (size of string loop) <r<(Gµ)1/2 (horizon size). The rotation velocity of galactic spirals in such halos is given by υrot=(4Gµ)1/2, which requires a value of µ ...
openaire +1 more source
Velocity Strings in Sultanate of Oman Gas Fields; A Case Study
SPE Conference at Oman Petroleum & Energy Show, 2022Abstract Petroleum Development Oman operates large amount of gas wells in Sultanate of Oman. Due to the liquid loading occurring in these ageing assets, PDO has already installed 110+ Velocity String completions in the various gas fields across the concession area. In the 2015–2019 period, 39 wells in the Saih Rawl field were retrofitted
openaire +1 more source
On the Vibrations of an Axially Moving String With a Time-Dependent Velocity
Volume 4B: Dynamics, Vibration, and Control, 2015The transverse vibrations of an axially moving string with a time-varying speed is studied in this paper. The governing equations of motion describing an axially moving string is analyzed using two different techniques. At first, the initial-boundary value problem is discretized using the Fourier sine series, and then the two timescales perturbation ...
Rajab A. Malookani, Wim T. van Horssen
openaire +1 more source
On the Flow Performance of Velocity Strings To Unload Wet Gas Wells
Proceedings of SPE Middle East Oil and Gas Show and Conference, 2007Abstract In depleted gas wells, the produced gas rate and consequently the velocity will drop to the extent that produced liquids are no longer carried to surface. The liquids accumulate in the well bore, increasing the sand face pressure.
openaire +1 more source
Velocity tracking control of an axially accelerating string and actuator system
Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304), 2003We present a control strategy for an axially moving string system that achieves vibration regulation along the string and ensures that the string tracks a desired axial velocity trajectory. The control strategy is implemented by utilizing the roller torque inputs applied at the entry and exit points of the string and a pair of control forces applied to
F. Zhang +4 more
openaire +1 more source
Peculiar velocities from cosmic strings
Physical Review D, 1987, Brandenberger +3 more
openaire +2 more sources
Velocity String Drainage Technology for Horizontal Gas Wells in Changbei
Processes, 2022Wenbin Cai
exaly