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Axial Flow Pumps
Published in Getu Hailu, Michal Varchola, Peter Hlbocan, Design of Hydrodynamic Machines, 2022
Getu Hailu, Michal Varchola, Peter Hlbocan
The geometry of many airfoil sections is uniquely defined by the National Advisory Committee for Aeronautics (NACA) designation for the airfoil. NACA identified and developed airfoil shapes in a logical manner in the 1930s. NACA airfoil classifications include NACA four-digit wing sections, NACA five-digit wing sections, and NACA six-series wing sections. NACA four-digit wing sections are designated as: NACA ABCDD. The first integer, A, indicates the maximum value of the mean camber line ordinate in percent of chord. The second integer, B, indicates the distance from the leading edge to the maximum camber location in tenths of chord. The last two integers, DD, indicate the maximum section thickness in percent of chord. NACA airfoil profiles can be generated with this four-digit information. An online tool, AeroToolbox (https://aerotoolbox.com/naca-4-series-airfoil-generator/), can be used to calculate, plot, and extract airfoil coordinates for any NACA four-digit series airfoil.
How and Why to Use Visible Knowledge
Published in Allen C. Ward, Dantar P. Oosterwal, Durward K. Sobek, Visible Knowledge for Flawless Designs, 2018
Allen C. Ward, Dantar P. Oosterwal, Durward K. Sobek
While the Wrights systematically developed limit information, they often left it in the form of tables rather than visual curves. The next generation of aeronautical engineers, however, brought visual knowledge to a peak of refinement. By the 1930s, the average aeronautical engineering paper was built around one or more curves. The National Advisory Committee for Aeronautics (NACA) published airfoil catalogs with sophisticated curves describing the relationships between Reynolds' numbers and lift and drag coefficients as a function of angle of attack—an enormous compression of information (Figure 1.13 shows an example of NACA airfoil curves). “Test to find limits, then design within the limits” was the order of the day.
Applications
Published in Raj P. Chhabra, CRC Handbook of Thermal Engineering Second Edition, 2017
Joshua D. Ramsey, Ken Bell, Ramesh K. Shah, Bengt Sundén, Zan Wu, Clement Kleinstreuer, Zelin Xu, D. Ian Wilson, Graham T. Polley, John A. Pearce, Kenneth R. Diller, Jonathan W. Valvano, David W. Yarbrough, Moncef Krarti, John Zhai, Jan Kośny, Christian K. Bach, Ian H. Bell, Craig R. Bradshaw, Eckhard A. Groll, Abhinav Krishna, Orkan Kurtulus, Margaret M. Mathison, Bryce Shaffer, Bin Yang, Xinye Zhang, Davide Ziviani, Robert F. Boehm, Anthony F. Mills, Santanu Bandyopadhyay, Shankar Narasimhan, Donald L. Fenton, Raj M. Manglik, Sameer Khandekar, Mario F. Trujillo, Rolf D. Reitz, Milind A. Jog, Prabhat Kumar, K.P. Sandeep, Sanjiv Sinha, Krishna Valavala, Jun Ma, Pradeep Lall, Harold R. Jacobs, Mangesh Chaudhari, Amit Agrawal, Robert J. Moffat, Tadhg O’Donovan, Jungho Kim, S.A. Sherif, Alan T. McDonald, Arturo Pacheco-Vega, Gerardo Diaz, Mihir Sen, K.T. Yang, Martine Rueff, Evelyne Mauret, Pawel Wawrzyniak, Ireneusz Zbicinski, Mariia Sobulska, P.S. Ghoshdastidar, Naveen Tiwari, Rajappa Tadepalli, Raj Ganesh S. Pala, Desh Bandhu Singh, G. N. Tiwari
Axial compressor blade design practices at first were closely related to aircraft airfoil design practices. In the United States, an NACA airfoil series, and in the United Kingdom, a circular arc airfoil series, were used by compressor designers as jet engines advanced in the 1950s. Wind tunnel tests of cascades of blades provided correlation of lift (angle change) and drag (losses) as a function of blade geometry, pitch/chord ratio, and stagger (blade angle relative to the axis).
An aerodynamic optimization design study on the bio-inspired airfoil with leading-edge tubercles
Published in Engineering Applications of Computational Fluid Mechanics, 2021
Yu Lu, Ziying Li, Xin Chang, Zhenju Chuang, Junhua Xing
It is worth noting that at α=4°, the CP on the lower surface of NACA airfoil is more uniform than that of four optimal airfoils, as a result the lift coefficient at this angle of attack is greater than that of the concave–convex airfoils. With the angle of attack growing, since the NACA airfoil come about stalling with sharp decrease of lift coefficient after the attack angle of 12°. But the lift coefficients of the bio-inspired airfoils continue to increase before stalling, where the pressure coefficient distribution of the bio-inspired airfoils gradually seems uniform. This is consistent with the results presented in Figure 14. Meanwhile the skin friction coefficient (CF) on the upper surface of the smooth airfoil and the four optimal airfoils in a wide range of attack angles α has been presented in Figures 18–20.
Development of an analytical model for the flexural vibration of fish bone active camber structures with truncated, variable thickness partitions
Published in Mechanics Based Design of Structures and Machines, 2022
Mahdi Nejati, Saeed Shokrollahi, Masoud Cheraghi
After establishing the validity of the developed formulation for partitioned plates of different heights that might also have variable thickness and be truncated along their edges, it is now time to consider a few cases for real scenarios where FishBAC is implemented. It was stated earlier that FishBAC can be built around different airfoils, which may or may not have a slope on their camber line in the trailing edge section. Accordingly, this article considers two different types of airfoils, i.e., a symmetric NACA 4-series airfoil and a cambered 5-digit NACA airfoil in different configurations. The results are then compared with the findings of COMSOL Multiphysics for different mode numbers.