Liner Rotation Research Articles

Shape manipulation of a rotating liquid liner imploded by arrays of pneumatic pistons: Experimental and numerical study

Shaping the inner surface of a rotating, imploding liquid metal liner as it compresses a magnetised plasma target is an important aspect of the Magnetised Target Fusion (MTF) scheme pursued by General Fusion. Reduced-order modelling has shown that the liner's inner surface shape can be manipulated during the implosion by spatially varying the amplitude and timing of pressure applied at the liner's outer surface. A sub-scale apparatus was constructed to investigate this concept, using water as the liner material. A simplified axisymmetric model of this apparatus was also developed using OpenFOAM software. Experimental pressure and rotational speed were used as inputs to numerical simulations. Very good agreement between numerical and experimental liner trajectories was obtained for a wide range of implosion parameters. Data analysis confirmed an initially cylindrical inner liner surface can be shaped and the shaped surface remains symmetrical to radial compression ratios of at least 7:1, despite driving the implosion using pneumatic piston arrays. Furthermore, experiments demonstrated suppression of Rayleigh-Taylor instability for shaped implosions by using liner rotation. This is significant, as literature only confirms this suppression for cylindrical implosions. These results increase confidence in simplified numerical modelling as a predictive tool for designing MTF machines.

The effect of glenoid component version and humeral polyethylene liner rotation on subluxation and impingement in reverse shoulder arthroplasty

A previously validated finite element modeling approach was used to determine how changes in glenoid component version and polyethylene liner rotation within the humeral component affect the arm abduction angle at which impingement between the inferior glenoid and the polyethylene liner occurs as well as the amount of subluxation generated by that impingement. Five glenoid component versions (5° anteversion; neutral; 5°, 10°, and 20° retroversion) and 7 polyethylene liner rotations (20° and 10° anterior; neutral; 10°, 20°, 30°, and 40° posterior) were considered, resulting in 35 different clinically representative models. The humerus was internally and externally rotated and extended and flexed, and the resulting impingement and subluxation were measured. To further analyze more global trends and to identify implantations least prone to subluxation, polyethylene liner rotation was additionally varied in coarser 30° increments across the entire 360° range. All subluxation caused by impingement occurred during external rotation and extension, and external rotation produced nearly 10-fold more subluxation than extension. Neutral glenoid component version was associated with the least amount of subluxation for all polyethylene liner rotations. Posteriorly rotated polyethylene liners, which place the thick inferior region of the component away from the scapula, produced the least amount of subluxation. The 90° and 120° posterior liner rotations produced no subluxation, whereas the 30° and 60° anterior liner rotations produced the greatest amount of subluxation. These results indicate that rotating modern radially asymmetric humeral polyethylene liners posteriorly can reduce the risk of subluxation leading to dislocation and increase external rotation range of motion.

Investigating the Benefits of Rotating-Liner Cementing and Impact Factors

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 180578, “Investigating the Benefits of Rotating-Liner Cementing and Impact Factors,” by Quek Khang Song, SPE, Hao Wang, and Weicun Dong, Halliburton, and Roger Bradshaw, SPE, Wei Cui, and Johnson Njoku, ConocoPhillips, prepared for the 2016 IADC/SPE Asia Pacific Drilling Technology Conference and Exhibition, Singapore, 22–24 August. The paper has not been peer reviewed. Effective primary cementing in the wellbore is critical to achieving positive wellbore isolation. This paper discusses an expandable-liner-hanger (ELH) system that provides liner rotation during the liner deployment and the cementing operation while providing a hydraulically energized liner-top seal upon setting. The case histories of the wells using the system verify the key consideration factors presented in this paper, which help improve the quality of the liner cementing bond. Liner-Hanger System The ELH system incorporates bonded elastomeric sections. The elastomeric element provides the hanging capacity for the liner and a gas-tight seal. The liner-hanger/packer body contains no setting mechanism or external components, such as slips, hydraulic cylinders, or pistons. The hydraulic setting mechanism is contained in the setting-tool assembly and is retrieved, eliminating potential leak paths in the flow stream. This running/setting-tool-assembly system provides the necessary expansion mechanics, cementing pack-off seals, a collet assembly to carry the liner weight and transfer the liner weight to the drillstring, and an end-of-expansion indicator assembly. As required, the liner system can be rotated and reciprocated when incorporated with an ELH high-torque running/setting tool and high-torque liner connections. The liner system can be rotated and reciprocated while running in the hole or during cementing operations (Fig. 1). Liner-Hanger Operation The key to a successful liner deployment is prejob planning. As part of the preplanning, several iterations of the torque-and-drag analysis are simulated with software to determine the ideal run-in-hole solution. The ELH system is run much like conventional liner-hanger systems, with minimal differences. The key difference is that the liner with the ELH system is cemented before setting the hanger because the hanger provides hydraulic isolation when it is set. Cementing before setting the liner hanger enables rotation and reciprocation, which should improve the cementing. No liner reciprocation during the cementing operation was planned because of rig limitations. In addition, rotation was preferred over reciprocation because the liner must be in the position across the zones of interest at all times and prevent any potential operational risk (e.g., stuck pipe or liner set high). The ELH standard setting/running tool has a torque rating limitation of 15,000 lbf-ft. Consequently, it was deployed as a non-rotational liner hanger. The ELH high-torque running/setting tool, with a torque rating of 39,071 lbf-ft, was used with the rotational liner-hanger system. During the cementing operation, the liner string was rotated at 10 to 20 rev/min. The next step is to set the hanger, which is performed hydraulically after releasing a set-ting ball. After the hanger is set, the liner top can be washed using conventional or reverse-circulation techniques. The tools are then retrieved from the wellbore, and the well is ready for completion.

Advanced Techniques Improve Liner Cementation in North Sea Wells: An Operator's Experience

Summary Improvements in liner cementation in the North Sea are being made through optimization of cementing practices and the use of advanced technology, which includes liner rotation during hole conditioning and cementing. This paper reviews our experiences and discusses key aspects of liner rotation, including equipment selection, job design, and implementation. Comparison of cement-bond logs (CBL's) with those from nonrotated-liner cement jobs shows that liner rotation during cementing can greatly improve results.

Field Results of Liner Rotation During Cementing

Summary Improving liner cementing has been a constant objective of the industry. Recent developments in rotating liner hanger technology have made this cementing technique applicable to more wells than before. Presented here is an analysis of 45 jobs done during 1 ½ years. The study examined mechanical success ratios as a function of liner size, depth, length, method of rotation, setting tool types, deviation, casing hardware (centralizers, scratchers, etc.), and bearing load. The results give the drilling and completion engineer a better understanding of the chances of a mechanically successful job.

Liner Rotation While Cementing: An Operator's Experience in South Texas

Summary The literature is replete with papers emphasizing the use of pipe movement while cementing to improve the opportunity for a successful primary cement job. Most operators, however, are reluctant to use liner movement, either reciprocation or rotation, while cementing. This paper reviews experiences with nine rotating liners in south Texas since Dec. 1983. The liner hanger system and procedure used in rotating while cementing is discussed. Mud types and weights, hole sizes vs. bit diameter, cement slurries and volumes, hole deviation, and torque encountered are reviewed. A postanalysis of each job, pressure and differential tests performed, and typical cement bond logs will be presented. Good primary liner cementing minimizes problems in production and stimulations and reduces cost. Liners were rotated throughout cement displacement on 77% of the jobs, while rotation was initiated on 88%. Liner rotation while cementing has improved the cement jobs and reduced the remedial cement work.

Liquid Metal Liner Implosion Systems with Blade Lattice for Fusion

In this paper, the liquid liner implosion systems with the blade lattice is proposed for the rotational stabilization of the liner inner surface which is facing a plasma in a fusion reactor. The blades are electrically conducting and inclined to the radial direction. Its major function is either acceleration or deceleration of the liner in the azimuthal direction. This system enables us to exclude the rotary mechanism for the liner rotation. In this system, the liner is formed as an annular flow of a liquid metal (the waterfall concept). Results show that there is no significant difference of the energy cost for the stabilization compared with the earlier proposed system where a liner is rotated rigidly before implosion. Furthermore, the application of the rotating blade lattice makes it possible to reduce the rotational kinetic energy required for the stabilization at turnaround, where the lattice acts as an impeller in the initial liner rotation. There is an optimum blade angle to maximize the compressed magnetic field energy inside the liner for a given driving energy.

Liquid metal liner implosion systems with blade lattice for fusion.

In this paper, the liquid liner implosion systems with the blade lattice is proposed for the rotational stabilization of the liner inner surface which is facing a plasma in a fusion reactor. The blades are electrically conducting and inclined to the radial direction. Its major function is either acceleration or deceleration of the liner in the azimuthal direction. This system enables us to exclude the rotary mechanism for the liner rotation. In this system, the liner is formed as an annular flow of a liquid metal (the waterfall concept). Results show that there is no significant difference of the energy cost for the stabilization compared with the earlier proposed system where a liner is rotated rigidly before implosion. Furthermore, the application of the rotating blade lattice makes it possible to reduce the rotational kinetic energy required for the stabilization at turnaround, where the lattice acts as an impeller in the initial liner rotation. There is an optimum blade angle to maximize the compresse...

DYNAMICS OF IMPLODING LINER FOR FLUX COMPRESSION

A solution of nonlinear equation of imploding rotating liner is derived in the incompressible model. The solution is applied, in the early stage of compressible liner implosion, for computer calculations of both one layer and two layer liners, which makes possible a significant reduction in the computation time. Energy balance and wave phenomenon in the liner are examined with use made of compressible hydrodynamics computer codes developed. Although the energy delivered to the liner rotation is large at the maximum compression, it strongly depends on the liner thickness and the angular velocity. In a liner with the angular velocity-shear, the rotation energy is found to be much reduced. In a two layer liner, a pressure wave reflected from the interface is also found to give important consequence to the liner dynamics.