Body Force Effects | ScienceGate

In this work, a Al-Cu-Li alloy plate with outstanding mechanical properties was successfully prepared with electromagnetic twin-roll casting (TRC) technology. The microstructure of Al-Cu-Li alloy manufactured by conventional mold casting, TRC, and electromagnetic TRC was studied in detail. The action mechanism of electromagnetic oscillation field (EOF) in the TRC process was studied by systematic experimental characterization and numerical simulation. The results show that the EOF will enlarge the circumfluence area in the cast-rolling zone, accelerate the mass transfer and heat transfer in the molten pool, and make the solute field and flow field in the liquid cavity tend to be evenly distributed. Further, the introduction of the EOF will produce the electromagnetic body force F with the maximum strength of 14 N/m3. The F acting on the solidification front will eliminate the accumulation and deposition of Cu2+, Li+, Mg2+, Zn2+, Mn2+ at the dendrite tip and inhibit the growth of dendrites. At the same time, the F can refine the microstructure of the TRC plate, promote the formation of equiaxed crystals, improve the supersaturated solid solubility of solute elements in the a(Al) matrix, and avoid the appearance of obvious solute segregation area or the formation of excessive solute enrichment area. Therefore, the macro-segregation in TRC plate was significantly reduced, the solidification structure was dramatically refined, and the comprehensive properties of the alloy were remarkably improved.

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Computational Modeling of Vortex Generators for Turbomachinery

Volume 5: Turbo Expo 2002, Parts A and B ◽

10.1115/gt2002-30677 ◽

2002 ◽

Cited By ~ 9

Author(s):

R. V. Chima

Keyword(s):

Computational Models ◽

Body Force ◽

Secondary Flows ◽

The Body ◽

Vortex Generators ◽

Force Model ◽

Suction Surface ◽

Near Surface ◽

Compressor Rotor ◽

Surface Particle

In this work computational models were developed and used to investigate applications of vortex generators (VGs) to turbomachinery. The work was aimed at increasing the efficiency of compressor components designed for the NASA Ultra Efficient Engine Technology (UEET) program. Initial calculations were used to investigate the physical behavior of VGs. A parametric study of the effects of VG height was done using 3-D calculations of isolated VGs. A body force model was developed to simulate the effects of VGs without requiring complicated grids. The model was calibrated using 2-D calculations of the VG vanes and was validated using the 3-D results. Then three applications of VGs to a compressor rotor and stator were investigated: 1. The results of the 3-D calculations were used to simulate the use of small casing VGs used to generate rotor preswirl or counterswirl. Computed performance maps were used to evaluate the effects of VGs. 2. The body force model was used to simulate large partspan splitters on the casing ahead of the stator. Computed loss buckets showed the effects of the VGs. 3. The body force model was also used to investigate the use of tiny VGs on the stator suction surface for controlling secondary flows. Near-surface particle traces and exit loss profiles were used to evaluate the effects of the VGs.

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Adaptations to Swimming Training in Athletes with Down’s Syndrome

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17249175 ◽

2020 ◽

Vol 17 (24) ◽

pp. 9175

Author(s):

José María González-Ravé ◽

Anthony P. Turner ◽

Shaun M. Phillips

Keyword(s):

Body Composition ◽

Body Force ◽

Swimming Performance ◽

Down's Syndrome ◽

Down’S Syndrome ◽

Training Intervention ◽

Countermovement Jump ◽

Swimming Training ◽

Jump Performance ◽

Swim Performance

Swimming training programs may help to limit declines in cardiovascular conditioning, muscle strength, mobility and social functioning in individuals with Down’s Syndrome (DS): (1) Background: This study aims to analyze the effects of a periodized swimming training program on swimming speed, lower body force and power and body composition in a group of swimmers with DS; (2) Methods: Nine swimmers with DS (2 men and 7 women; aged 21–30 years-old) completed an 18-week periodized swimming program. The swimmers were assessed, pre and post-training, for 25 m, 50 m and 100 m freestyle swim performance, countermovement jump performance and body composition; (3) Results: Significant and large improvements in 25 m (mean −6.39%, p < 0.05, d = 1.51), 50 m (mean −4.95%, p < 0.01, d = 2.08) and 100 m (mean −3.08%, p < 0.05, d = 1.44) freestyle performance were observed following training, with no significant changes in body composition or consistent changes in jump performance (although a large mean 14.6% decrease in relative peak force, p < 0.05, d = 1.23) (4) Conclusions: A periodized 18-week training intervention may improve swimming performance in a small group of trained swimmers with DS, with less clear changes in jump performance or body composition. This program provides a training profile for coaches working with swimmers with DS and a platform for further research into the benefits of swimming training with this under-represented population.

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Three body force model for lattice dynamics of copper

Solid State Communications ◽

10.1016/0038-1098(86)90320-0 ◽

1986 ◽

Vol 57 (8) ◽

pp. 559-562 ◽

Cited By ~ 6

Author(s):

H. Nait-Laziz ◽

K.K. Chopra

Keyword(s):

Lattice Dynamics ◽

Body Force ◽

Force Model ◽

Three Body

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