Institution
National Aerospace Laboratories
Facility•Bengaluru, India•
About: National Aerospace Laboratories is a facility organization based out in Bengaluru, India. It is known for research contribution in the topics: Coating & Corrosion. The organization has 1838 authors who have published 2349 publications receiving 36888 citations.
Topics: Coating, Corrosion, Mach number, Sputter deposition, Aerodynamics
Papers published on a yearly basis
Papers
More filters
••
TL;DR: In this article, the effect of the relative azimuthal orientation of the cross wires, placed at the exit of two identical converging-diverging nozzles, on the flow field of the twin jet is studied experimentally.
18 citations
••
TL;DR: In this paper, a modified SHS route under pressure was used to obtain a body centered tetragonal C11b phase below x lt; 0.05 substitution, above which a biphasic region of C40 structure coexisted, and aluminum substitution leads to a continuous increase in the lattice parameters in both these structures.
18 citations
••
TL;DR: In this article, a method of generating comprehensive longitudinal aerodynamic data of aircraft using dynamic wind-tunnel simulation is presented, which utilizes the motion and force responses of an aircraft model to control surface inputs to determine trim lift characteristics, longitudinal stability derivatives, and neutral point.
Abstract: A novel method of generating comprehensive longitudinal aerodynamic data of aircraft using dynamic wind-tunnel simulation is presented. The method utilizes the motion and force responses of an aircraft model to control surface inputs to determine trim lift characteristics, longitudinal stability derivatives, and neutral point. In addition, large-amplitude lift and pitching moment responses characterizing the unsteady aerodynamic behavior are also generated using the same experimental setup. The new test method is demonstrated using a generic delta wing aircraft model with one degree of freedom in pitch. The model pitch attitude and lift force responses to elevon dynamic inputs are measured and used to deduce longitudinal aerodynamic data. Comparison of these results with static test data and Datcom estimates shows good agreement. Nomenclature CL = lift coefe cient, L/qS CLa = lift curve slope, rad 21
18 citations
••
TL;DR: In this paper, an anodic oxide layer was developed on AA2024 specimens by sulfuric acid anodization process and subsequently sealed with chromate free Mn-Mo oxyanions (PMMO) by simple dip method.
Abstract: In the present investigation, an anodic oxide layer was developed on AA2024 specimens by sulfuric acid anodization process and subsequently sealed with chromate free Mn–Mo oxyanions (PMMO) by simple dip method. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy studies showed the presence of multiple oxidation states of Mn and Mo and the polymolybdate in the sealed anodic oxide layer respectively. Various electrochemical techniques were used to evaluate the corrosion performance of the developed coatings. Cyclic polarization test results showed a wide trans-passive potential region (> 2 V) for PMMO. Electrochemical noise measurement (ENM) results revealed pit growth of PMMO is highly controlled due to the presence of inhibitors in the sealed oxide layer. Scanning vibrating electrode technique (SVET) results revealed a minimal localized distribution of anodic and cathodic corrosion sites on PMMO compared to plain oxide layer (PO) and HTO after 168 h of immersion in 0.6 M NaCl solution. The results obtained from electrochemical impedance spectroscopy (EIS) showed one to two orders magnitude higher impedance (│Z│0.1 Hz) value for PMMO compared to PO and HTO. Neutral salt spray test result of PMMO after 1000 h showed comparable corrosion performance with conventional chromic acid anodized (CAA) specimen.
18 citations
••
27 Jun 2011TL;DR: In this paper, an experimental study has been carried out on a typical Micro Air Vehicle of span 300mm having inverse Zimmerman planform and the objective is to get i) the aerodynamic characteristics of the vehicle in the range of incidence and sideslip angle the vehicle expected to encounter during its flight; ii) an understanding of the propeller effect on aerodynamic data and iii) the control surface (elevon) effectiveness with incidence.
Abstract: An experimental study has been carried out on a typical Micro Air Vehicle of span 300mm having inverse Zimmerman planform. The objective is to get i) the aerodynamic characteristics of the vehicle in the range of incidence and sideslip angle the vehicle expected to encounter during its flight; ii) an understanding of the propeller effect on the aerodynamic data and iii) the control surface (elevon) effectiveness with incidence. Tests were carried out in a low speed wind tunnel at a freestream velocity of 8 m/s and 12 m/s corresponding to a test Reynolds number based on chord of about 120000 and 180000 respectively. Analysis of the aerodynamic data showed significant effect of propeller flow field on the lift, stall angle and drag of the vehicle. The propeller induced flow is seen to increase the lift coefficient at higher angle of attack and delay the stall. Nonlinear variation is observed in the rolling moment indicating the onset of asymmetric flow field at higher incidence. The effectiveness of the elevon is observed to increase linearly with incidence.
17 citations
Authors
Showing all 1850 results
Name | H-index | Papers | Citations |
---|---|---|---|
Harish C. Barshilia | 46 | 236 | 6825 |
K.S. Rajam | 42 | 83 | 4765 |
Kozo Fujii | 39 | 411 | 5845 |
Parthasarathi Bera | 39 | 136 | 5329 |
R.P.S. Chakradhar | 36 | 166 | 4423 |
T. N. Guru Row | 36 | 309 | 5186 |
Takashi Ishikawa | 36 | 154 | 5019 |
Henk A. P. Blom | 34 | 168 | 5992 |
S. Ranganathan | 33 | 211 | 5660 |
S.T. Aruna | 33 | 101 | 4954 |
Arun M. Umarji | 33 | 207 | 3582 |
Vinod K. Gaur | 33 | 92 | 4003 |
Keisuke Asai | 31 | 350 | 3914 |
K. J. Vinoy | 30 | 240 | 3423 |
Gangan Prathap | 30 | 241 | 3466 |