Author: Sharon K. StanawayPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Navier-Stokes Analysis of Blunt Trailing Edge Airfoils
Author: Sharon K. StanawayBlunt Trailing Edge Analysis of Supercritical Airfoils by a Navier-Stokes Code
Author: Aerodynamic Analysis of Blunt Trailing Edge Airfoils & a Micro-based Load Control System
Author: Kevin James StandishPublisher:
ISBN:
Category :
Languages : en
Pages : 330
Book Description
Wind Tunnel and Numerical Analysis of Thick Blunt Trailing Edge Airfoils
Author: Anthony William McLennanPublisher:
ISBN: 9781124509174
Category :
Languages : en
Pages :
Book Description
Two-dimensional aerodynamic characteristics of several thick blunt trailing edge airfoils are presented. These airfoils are not only directly applicable to the root section of wind turbine blades, where they provide the required structural strength at a fraction of the material and weight of an equivalent sharp trailing edge airfoil, but are also applicable to the root sections of UAVs having high aspect ratios, that also encounter heavy root bending forces. The Reynolds averaged Navier-Stokes code, ARC2D, was the primary numerical tool used to analyze each airfoil. The UCD-38-095, referred to as the Pareto B airfoil in this thesis, was also tested in the University of California, Davis Aeronautical Wind Tunnel. The Pareto B has an experimentally determined maximum lift coefficient of 1.64 at 14 degrees incidence, minimum drag coefficient of 0.0385, and maximum lift over drag ratio of 35.9 at a lift coefficient of 1.38, 10 degrees incidence at a Reynolds number of 666,000. Zig-zag tape at 2% and 5% of the chord was placed on the leading edge pressure and suction side of the Pareto B model in order to determine the aerodynamic performance characteristics at turbulent flow conditions. Experimental Pareto B wind tunnel data and previous FB-3500-0875 data is also presented and used to validate the ARC2D results obtained in this study. Additionally MBFLO, a detached eddy simulation Navier-Stokes code, was used to analyze the Pareto B airfoil for comparison and validation purposes.
Navier-Stokes Analysis of Airfoils with Leading Edge Ice Accretions
Author: Drag Reduction of a Blunt Trailing-edge Airfoil
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Wind-tunnel experimentation and Reynolds-averaged Navier-Stokes simulations were used to analyze simple, static trailing-edge devices applied to an FB-3500-1750 airfoil, a 35% thick airfoil with a 17.5% chord blunt trailing edge, in order to mitigate base drag. The drag reduction devices investigated include Gurney-type tabs, splitter plates, base cavities, and offset cavities. The Gurney-type tabs consisted of small tabs, attached at the trailing edge and distributed along the span, extending above the upper and lower surfaces of the airfoil. The Gurney-type devices were determined to have little drag reduction capabilities for the FB-3500-1750 airfoil. Splitter plates, mounted to the center of the trailing edge, with lengths between 50% and 150% of the trailing-edge thickness and various plate angles (0° and "10° from perpendicular) were investigated and shown to influence the lift and drag characteristics of the baseline airfoil. Drag reductions of up to 50% were achieved with the addition of a splitter plate. The base cavity was created by adding two plates perpendicular to the trailing edge, extending from the upper and lower surfaces of the airfoil. The base cavity demonstrated possible drag reductions of 25%, but caused significant changes to lift, primarily due to the method of device implementation. The offset cavity, created by adding two splitter plates offset from the upper and lower surfaces by 25% of the trailing-edge thickness, was shown to improve on the drag reductions of the splitter plate, while also eliminating unsteady vortex shedding prior to airfoil stall.
Navier-Stokes Analysis of Airfoils with Leading Edge Ice Accretions
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781724317056
Category :
Languages : en
Pages : 208
Book Description
A numerical analysis of the flowfield characteristics and the performance degradation of an airfoil with leading edge ice accretions was performed. The important fluid dynamic processes were identified and calculated. Among these were the leading edge separation bubble at low angles of attack, complete separation on the low pressure surface resulting in premature shell, drag rise due to the ice shape, and the effects of angle of attack on the separated flow field. Comparisons to experimental results were conducted to confirm these calculations. A computer code which solves the Navier-Stokes equations in two dimensions, ARC2D, was used to perform the calculations. A Modified Mixing Length turbulence model was developed to produce grids for several ice shape and airfoil combinations. Results indicate that the ability to predict overall performance characteristics, such as lift and drag, at low angles of attack is excellent. Transition location is important for accurately determining separation bubble shape. Details of the flowfield in and downstream of the separated regions requires some modifications. Calculations for the stalled airfoil indicate periodic shedding of vorticity that was generated aft of the ice accretion. Time averaged pressure values produce results which compare favorably with experimental information. A turbulence model which accounts for the history effects in the flow may be justified. Potapczuk, Mark G. Unspecified Center NASA-CR-191008, E-7580, NAS 1.26:191008 NAG3-416; RTOP 505-68-10...
Scientific and Technical Aerospace Reports
Author: An Analysis of the Crossover Between Local and Massive Separation on Airfoils
Author: Mark BarnettPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 112
Book Description
An Analysis of the Crossover Between Local and Massive Separation on Airfoils
Author: M. BurnettPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 112
Book Description