A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
S., Nithya
- Design And Performance Analysis Of Bump Surface In An Airfoil
Authors
Source
International Journal of Innovative Research and Development, Vol 2, No 11 (2013), Pagination:Abstract
The performance of an airplane wing is often degraded by flow separation. Flow separation on an airfoil surface is related to the aerodynamic design of the airfoil profile. In order to obtain the best performance efficiencies for mission in aircraft, it is necessary to either: (a) alter the boundary layer behavior over the airfoil surface-flow control methods, or (b) change the geometry of the airfoil for changing free stream conditions- adaptive wing technology. The objective of this project work is to delay the flow separation point over the airfoil and increase the stall angle. This project deals about the effect of bump surface on the aircraft wing and also will give an over view of the results that is obtained for drag reduction by the creation of bump. In this paper the boundary layer and its controls are discussed.
After the airfoil profile generation and meshing the performance calculation had been carried out to evaluate the variation of angle of attacks, co-efficient of lift, and co-efficient of drag. The results obtained for with bump airfoil is compared with the airfoil without bump. The stall angle has increased from 23 to 24 by the creation of leading edge bump in an airfoil.
The designing of the airfoil with a bump and meshing is done by using GAMBIT. The analysis of fluid separation in an airfoil due to various locations of bumps and its effects on the aerodynamic forces is performed using FLUENT. This analysis is performed at a low velocity of 50m/s.
Keywords
Airfoil , Reynolds Number, Micro Air vehicles, Angle of attack, Flow separation, Stalling angle, Bump surface- Theoretical Investications on Geometric and Electronic Structure, Bonding and Spectral Properties of Dimolybdaboranes (CpMo)2B5H8 X (X = H, OH, OC6H5)
Authors
1 Department of Chemistry, Mahendra Arts and Science College (Autonomous), Kalippatti, Namakkal – 637501, Tamil Nadu, IN
2 Department of Chemistry, Vivekanandha College of Arts and Sciences for women (Autonomous), Tiruchengode – 637205, Namakkal, Tamil Nadu, IN
Source
ScieXplore: International Journal of Research in Science, Vol 5, No 2 (2018), Pagination: 1-7Abstract
Density Functional Theory calculations are used to address both the geometrical and electronic structural features, bonding and magnetic properties of the group 6 dimetallaboranes which includes, dimolybedaboranes of the type (CpMo)<sub>2</sub>(B<sub>5</sub>H<sub>9</sub>) (1), and its derivatives (CpMo)<sub>2</sub> (B<sub>4</sub> H<sub>8</sub> X) (X = OH (2), OC<sub>6</sub>H<sub>5</sub> (3)). Compound (CpMo)<sub>2</sub>B<sub>5</sub>H<sub>9</sub> (1) is experimentally known and compounds 2 and 3 are new molybdenum analogues. DFT (BP86/TZVP) computed metrical parameters and electronic and spectral properties are in good agreement with the experimental values of related clusters and suggest the stability and possible synthesis of new clusters (CpMo)<sub>2</sub>(B<sub>4</sub>H<sub>8</sub>OH) 2 and CpMo)<sub>2</sub> (B<sub>4</sub>H<sub>8</sub>OPh) 3.Keywords
Metallaborane, Spectroscopy, DFTReferences
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