Fluid–Structure Interaction in the Flexible Porous Stratification Manifold

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Shuping Wang ◽  
Jane H. Davidson
Keyword(s):  
Fluid Structure Interaction ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Neutral Buoyancy ◽  
Cross Sectional ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Water Heaters ◽  
Solar Water Heaters ◽  
Vertical Level

A model of the flexible porous manifold that captures the interaction between the flow field and the deformation of the manifold is developed and applied to understand how the fabric manifold works for conditions expected in solar water heaters. Contrary to the widely held hypothesis that the change of cross-sectional area induced by the fluid–structure interaction is beneficial, the numerical results demonstrate the change of cross-sectional area has no significant impact on the effectiveness of the manifold. In comparison to a rigid porous manifold, the performance of the flexible manifold is slightly worse because the collapse of the manifold encourages entrainment. The dimensionless permeability plays a crucial role in determining the performance and can be selected to limit entrainment and release fluid near the vertical level of neutral buoyancy.

A Moored Arctic Floater in First-Year Sea Ice Ridges

2015 ◽  
Vol 137 (1) ◽  
Author(s):  
Oddgeir Dalane ◽  
Vegard Aksnes ◽  
Sveinung Løset
Keyword(s):  
Sea Ice ◽  
Cross Sectional Area ◽  
The Arctic ◽  
First Year ◽  
Sectional Area ◽  
Cross Sectional ◽  
Ridge Structure ◽  
Structure Interaction ◽  
Ship Model ◽  
Mooring Forces

First-year sea ice ridges are a major concern for structures operating in the Arctic offshore and will in many cases give the design mooring load. In this paper, the response of a moored conical floater, somewhat similar to the well-known Kulluk, is studied in first-year ridges. The study is based on model tests performed at Hamburg Ship Model Basin (HSVA) in several ridges with different properties. Mooring forces and floater response, resulting from interaction with different ridges, were compared with respect to ridge properties, ridge behavior, and simulated ice management. Clearance of accumulated rubble upstream the structure was the dominating physical process in the ridge–structure interaction. Accumulation of rubble caused large mooring forces. The amount of accumulated rubble depended on the ridge cross-sectional area, thus the mooring forces increased with ridge cross-sectional area. Large mooring forces were also experienced after the ridge was passed by the structure due to difficulties with clearing of accumulated rubble.

A Moored Arctic Floater in First-Year Sea Ice Ridges

2009 ◽  
Author(s):  
Oddgeir Dalane ◽  
Vegard Aksnes ◽  
Sveinung Lo̸set ◽  
Jan Vidar Aarsnes
Keyword(s):  
Sea Ice ◽  
Initial Position ◽  
Cross Sectional Area ◽  
The Arctic ◽  
First Year ◽  
Sectional Area ◽  
Cross Sectional ◽  
Ridge Structure ◽  
Structure Interaction ◽  
Mooring Forces

First-year sea ice ridges are a major concern for structures operating in the Arctic and will in many cases give the design mooring load. In this paper, a moored conical floater, somewhat similar to the well-known Kulluk, is studied in first-year ridges. The study is based on model tests performed at HSVA in several ridges with different properties. Mooring forces and floater response resulting from interaction with different ridges were compared with respect to ridge properties, ridge behaviour and simulated ice management. Clearance of accumulated rubble upstream the structure was the dominating physical process in the ridge-structure interaction. Accumulation of rubble caused large mooring forces. The amount of accumulated rubble depended on the ridge cross-sectional area, thus the mooring forces increased with ridge cross-sectional area. Large mooring forces were also experienced after the initial position of the ridge was passed due to difficulties with clearing of accumulated rubble.

scholarly journals Thermal Performance of Solar Hot Water Systems Using a Flat Plate Collector of Accelerated Risers

2012 ◽  
Vol 9 (1) ◽  
pp. 1 ◽  
Author(s):  
KE Amori ◽  
NS Jabouri
Keyword(s):  
Tilt Angle ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
The Other ◽  
Sectional Area ◽  
Cross Sectional ◽  
Water Heaters ◽  
Flat Plate Collector ◽  
Solar Water Heaters

 This study focuses on a comparison of the performance of two similar locally-fabricated solar water heaters. One of the collectors features a new design for accelerated absorber; its risers are made of converging ducts whose exit area is half that of the entrance. The other collector is a conventional absorber, with risers of the same cross sectional area along its length. Each collector is the primary part of an indirect thermosyphon circulation solar hot water system. Both collectors face south with a fixed tilt angle of 33.3

Pelvic Canal Narrowing Caused by Triple Pelvic Osteotomy in the Dog

1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani
Keyword(s):  
Postoperative Complications ◽  
Pelvic Osteotomy ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Canal Width ◽  
Operative Complications ◽  
Post Operative Complications

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.

Sign in / Sign up

Export Citation Format

Share Document