On the Response of Elastic-Plastic Tubes Under Combined Bending and Tension

1992 ◽  
Vol 114 (1) ◽  
pp. 50-62 ◽  
Author(s):  
J. Y. Dyau ◽  
S. Kyriakides
Keyword(s):  
Numerical Simulation ◽  
Parametric Study ◽  
Axial Load ◽  
Test Specimen ◽  
Experimental Results ◽  
Two Dimensional ◽  
Plastic Range ◽  
Rigid Surface ◽  
Axial Tension ◽  
Thin Walled

This paper is concerned with the response of long, relatively thin-walled tubes bent into the plastic range in the presence of axial tension. The work is motivated by the design needs of pipelines installed and operated in deep offshore waters. The problem is studied through a combination of experiment and analysis. In the experiments, long metal tubes were bent over a smooth, circular, rigid surface (mandrel). Bending of the tubes was achieved by shear and axial end loads. The experimental arrangement is such that a significant section of the test specimen is loaded and deformed in an axially uniform fashion. The ovalization induced in the specimen was measured as a function of the axial load in the tube for two mandrel radii. A two-dimensional numerical simulation of the problem has been developed and validated against the experimental results. This analysis was used to conduct a parametric study of the effect of tension on the ovalization induced in a long tube during bending.

Numerical Simulation of Zone-Melting Recrystallization of Thin Silicon Films With A Tungsten Halogen Lamp

1991 ◽  
Vol 235 ◽  
Author(s):  
Richard D. Robinson ◽  
Ioannis N. Miaoulis
Keyword(s):  
Numerical Simulation ◽  
Parametric Study ◽  
Thermal Effects ◽  
Zone Melting ◽  
Incandescent Lamp ◽  
Silicon Films ◽  
Halogen Lamp ◽  
Two Dimensional ◽  
Thin Silicon ◽  
Tungsten Halogen Lamp

ABSTRACTA two dimensional numerical simulation of incandescent lamp Zone-Melting Recrystallization (ZMR) was performed. A parametric study examined the thermal effects of lamp intensity, susceptor temperature, and ambient reflectivity, on the melt zone. The melt zone was found to vary linearly with lamp intensity and parabolically with susceptor temperature and ambient reflectivity.

Axial and Moment Carrying Capacity of Split Sleeve Grouted Connections for Repair of Tubular Members

2019 ◽  
Author(s):  
N. Vignesh Chellappan ◽  
S. Nallayarasu
Keyword(s):  
Numerical Simulation ◽  
Carrying Capacity ◽  
Parametric Study ◽  
Load Transfer ◽  
Element Model ◽  
Offshore Structures ◽  
Geometric Parameters ◽  
Axial Tension ◽  
Load Transfer Mechanism ◽  
Comprehensive Study

Abstract The tubular members damaged by ship impact or falling objects require repair and rehabilitation in offshore structures. The repair of damaged underwater tubular member using welding is hazardous and expensive and hence alternative connection methods such as grouted clamp techniques have been in use for many decades. The existing guideline on the design of grouted connections especially under axial tension and moment is very limited and requires further study. The load transfer mechanism of grouted clamps depends on various geometric parameters and bond between clamp and parent member. A comprehensive study on split sleeve grouted connection for load transfer between two parts of tubular members has been investigated and presented. Numerical simulation of split sleeve grouted connection has been carried out using finite element model of tubular member – sleeve through bond strength of grout. The numerical model has been validated using existing guidelines and further parametric study has been carried out. The parametric study includes geometric parameters such as diameter to wall thickness ratio of split sleeve, sleeve friction length, grout strength and grout shrinkage. The simulations have been carried out for combination of axial tension and moment loading.

scholarly journals Is contact angle a cause or an effect? – A cautionary tale

2020 ◽  
Vol 146 ◽  
pp. 03004
Author(s):  
Douglas Ruth
Keyword(s):  
Contact Angle ◽  
Solid Surface ◽  
Contact Angles ◽  
Two Dimensions ◽  
Experimental Results ◽  
Flow In Porous Media ◽  
Two Dimensional ◽  
Wide Range ◽  
Fluid Drop ◽  
Surrounding Fluid

The most influential parameter on the behavior of two-component flow in porous media is “wettability”. When wettability is being characterized, the most frequently used parameter is the “contact angle”. When a fluid-drop is placed on a solid surface, in the presence of a second, surrounding fluid, the fluid-fluid surface contacts the solid-surface at an angle that is typically measured through the fluid-drop. If this angle is less than 90°, the fluid in the drop is said to “wet” the surface. If this angle is greater than 90°, the surrounding fluid is said to “wet” the surface. This definition is universally accepted and appears to be scientifically justifiable, at least for a static situation where the solid surface is horizontal. Recently, this concept has been extended to characterize wettability in non-static situations using high-resolution, two-dimensional digital images of multi-component systems. Using simple thought experiments and published experimental results, many of them decades old, it will be demonstrated that contact angles are not primary parameters – their values depend on many other parameters. Using these arguments, it will be demonstrated that contact angles are not the cause of wettability behavior but the effect of wettability behavior and other parameters. The result of this is that the contact angle cannot be used as a primary indicator of wettability except in very restricted situations. Furthermore, it will be demonstrated that even for the simple case of a capillary interface in a vertical tube, attempting to use simply a two-dimensional image to determine the contact angle can result in a wide range of measured values. This observation is consistent with some published experimental results. It follows that contact angles measured in two-dimensions cannot be trusted to provide accurate values and these values should not be used to characterize the wettability of the system.

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