The Density of Coextruded Metal Cladded Rod Core as Function of Cartridge Density and Core Length

Abstract Experiments and simulations were carried on C-D nozzles with four different exit geometry aspect ratios to investigate the impact of supersonic decay characteristics. Rectangular and elliptical exit geometries were considered for the study with various aspect ratios. Numerical simulations and Schlieren image study were studied and found the agreeable logical physics of decay and spread characteristics. The supersonic core decay was found to be of different length for different exit geometry aspect ratio, though the throat to exit area ratio was kept constant to maintain the same exit Mach number. The impact of nozzle exit aspect ratio geometry was responsible to enhance the mixing of primary flow with ambient air, without requiring a secondary method to increase the mixing characteristics. The higher aspect ratio resulted in better mixing when compared to lower aspect ratio exit geometry, which led to reduction in supersonic core length. The behavior of core length reduction gives the identical signature for both under-expanded and over-expanded cases. The results revealed that higher aspect ratio of the exit geometry produced smaller supersonic core length. The aspect ratio of cross section in divergent section of the nozzle was maintained constant from throat to exit to reduce flow losses.

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Heat Transfer and Solidification Model of Slab Continuous Casting Based on Nail-Shooting Experiments

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1088.153 ◽

2015 ◽

Vol 1088 ◽

pp. 153-158 ◽

Cited By ~ 1

Author(s):

An Gui Hou ◽

Yi Min ◽

Cheng Jun Liu ◽

Mao Fa Jiang

Keyword(s):

Heat Transfer ◽

Continuous Casting ◽

Liquid Core ◽

Casting Process ◽

Soft Reduction ◽

Slab Continuous Casting ◽

Solidification Model ◽

Core Length ◽

Measurement Results ◽

Heat Transfer And Solidification

A heat transfer and solidification model of slab continuous casting process was developed, and the nail-shooting experiments were carried out to verify and improve the prediction accuracy. The comparison between the simulation and the measurements results showed that, there exists difference between the model predicted liquid core length and the calculated liquid core length according to the measurement results of the solidification shell thickness. In the present study, the value of constant a in the heat transfer coefficient calculation formula was corrected through back-calculation, results showed that, the suitable value of a is 31.650, 33.468 and 35.126 when the casting speed is 0.8m·min-1, 0.9m·min-1 and 1.0m·min-1 respectively, which can meet the liquid core length of the measurement results. The developed model built a foundation for the application of dynamic secondary cooling, and dynamic soft reduction.

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Nucleosome reconstitution of core-length poly(dG.cntdot.poly(dC) and poly(rG-dC).cntdot.poly(rG-dC)

Biochemistry ◽

10.1021/bi00429a009 ◽

1989 ◽

Vol 28 (3) ◽

pp. 975-980 ◽

Cited By ~ 8

Author(s):

Sumedha D. Jayasena ◽

Michael J. Behe

Keyword(s):

Core Length

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Effect of flat wall length on decay and shock structure of a supersonic square wall jet

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/09544100211058016 ◽

2021 ◽

pp. 095441002110580

Author(s):

Venkata Satya Manikanta Tammabathula ◽

Venkata Sai Krishna Ghanta ◽

Tharaka Narendra Sridhar Bandla

Keyword(s):

Supersonic Jet ◽

Leading Edge ◽

Shock Structure ◽

Wall Jet ◽

Pressure Measurements ◽

Maximum Enhancement ◽

Flat Wall ◽

Decay Behaviour ◽

Core Length ◽

Supersonic Core Length

Experiments were conducted to find the effect of wall length on the decay behaviour and shock structure of a supersonic wall jet issuing from c-d nozzle of the square-shaped exit. A straight flat wall of width same as the side length of the square was attached to the lip of the nozzle such that the leading edge of the wall and the side of the square aligned properly which allowed the supersonic jet to graze past the flat wall. Experiments were conducted with five different wall lengths, that is, [Formula: see text] = 0.5, 1, 2, 4 and 8. Wall pressure measurements were made from leading edge to the trailing edge of the wall along its centreline. Schlieren flow visualization of the jet flow over the wall for the different wall lengths revealed the shock pattern and the effect of the wall length on the shock structure. The shock structure and jet deflection were significantly affected due to the presence of the wall. There was an upward jet deflection for [Formula: see text] up to [Formula: see text] whereas a downward jet deflection was observed for [Formula: see text]. Noticeable changes in the shock structure were observed for the wall lengths up to 2 D h. The wall length also significantly affected the jet decay characteristics and supersonic core length. Maximum enhancement in jet decay and maximum reduction in supersonic core length resulted when the wall length was [Formula: see text]. However, when the wall length was increased to [Formula: see text], there was a significant reduction in jet decay and a recovery of [Formula: see text]. Presence of wall always resulted a reduction in Lsc irrespective of wall length. The wall effect was to induce a more precipitous pressure drop closer to the nozzle exit, and a more gradual drop farther from it for [Formula: see text] > [Formula: see text].

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Nitrous Oxide and Carbon Dioxide Emissions from Aerobic and Anaerobic Incubations: Effect of Core Length

Soil Science Society of America Journal ◽

10.2136/sssaj2012.0292 ◽

2013 ◽

Vol 77 (3) ◽

pp. 817-829 ◽

Cited By ~ 7

Author(s):

Xiaobin Guo ◽

Craig F. Drury ◽

W. Daniel Reynolds ◽

Xueming Yang ◽

Ruqin Fan

Keyword(s):

Carbon Dioxide ◽

Nitrous Oxide ◽

Carbon Dioxide Emissions ◽

Core Length ◽

Aerobic And Anaerobic

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Numerical predictions of the flow characteristics of subsonic jet emanating from corrugated lobed nozzle

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-03-2019-0041 ◽

2020 ◽

Vol 92 (7) ◽

pp. 955-972

Author(s):

Roy V. Paul ◽

Kriparaj K.G. ◽

Tide P.S.

Keyword(s):

Flow Characteristics ◽

Experimental Results ◽

Potential Core ◽

Content Type ◽

Numerical Predictions ◽

Core Length ◽

Chevron Nozzle ◽

Centreline Velocity ◽

Subsonic Jet ◽

Lobed Nozzle

Purpose The purpose of this study is to investigate the aerodynamic characteristics of subsonic jet emanating from corrugated lobed nozzle. Design/methodology/approach Numerical simulations of subsonic turbulent jets from corrugated lobed nozzles using shear stress transport k-ω turbulence model have been carried out. The analysis was carried out by varying parameters such as lobe length, lobe penetration and lobe count at a Mach number of 0.75. The numerical predictions of axial and radial variation of the mean axial velocity, u′u′ ¯ and v′v′ ¯ have been compared with experimental results of conventional round and chevron nozzles reported in the literature. Findings The centreline velocity at the exit of the corrugated lobed nozzle was found to be lower than the velocity at the outer edges of the nozzle. The predicted potential core length is lesser than the experimental results of the conventional round nozzle and hence the decay in centreline velocity is faster. The centreline velocity increases with the increase in lobe length and becomes more uniform at the exit. The potential core length increases with the increase in lobe count and decreases with the increase in lobe penetration. The turbulent kinetic energy region is narrower with early appearance of a stronger peak for higher lobe penetration. The centreline velocity degrades much faster in the corrugated nozzle than the chevron nozzle and the peak value of Reynolds stress appears in the vicinity of the nozzle exit. Practical implications The corrugated lobed nozzles are used for enhancing mixing without the thrust penalty inducing better acoustic benefits. Originality/value The prominent features of the corrugated lobed nozzle were obtained from the extensive study of variation of flow characteristics for different lobe parameters after making comparison with round and chevron nozzle, which paved the way to the utilization of these nozzles for various applications.

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