Last edited by Dashakar
Monday, May 18, 2020 | History

3 edition of Finite-difference computations of rotor loads found in the catalog.

Finite-difference computations of rotor loads

Finite-difference computations of rotor loads

  • 139 Want to read
  • 0 Currently reading

Published by National Aeronautics and Space Administration, Ames Research Center, For sale by the National Technical Information Service, U.S. Army Aviation Systems Command in Moffett Field, Calif, [Springfield, Va, St. Louis, Mo .
Written in English

    Subjects:
  • Rotors (Helicopters) -- Aerodynamics.

  • Edition Notes

    Other titlesFinite difference computations of rotor loads.
    StatementF. X. Caradonna, C. Tung.
    SeriesNASA technical memorandum -- 86682., USAAVSCOM technical report -- 85-A-3., AVSCOM technical report -- 85-A-3.
    ContributionsTung, C. 1936-, United States. Army Aviation Systems Command., Ames Research Center.
    The Physical Object
    FormatMicroform
    Pagination1 v.
    ID Numbers
    Open LibraryOL18028959M

      Conservative full-potential model for unsteady transonic rotor flows. Computation of rotor aerodynamic loads with a constant vorticity contour free wake model. A CONSERVATIVE IMPLICIT FINITE DIFFERENCE ALGORITHEM FOR THE Cited by: For a rapid rotor flow field computation, an efficient NS code, TLNS3DR, has been developed from an existing multigrid fixed-wing code, TLNS3D. The TLNS3DR is a modified version of the TLNS3D code with addition of rotation terms for use in rotary-wing by: 4.

      American Institute of Aeronautics and Astronautics Sunrise Valley Drive, Suite Reston, VA Cited by: •The phase relation between the rotor and stator magnetic field (i.e. the load angle) must be always greater than 0°in order to keep the motor in motion (negative angles reverse the rotation). •Output torque depends on both the solenoid current and load angle. •Motor rotation causes a back electro-motive force opposing the motion itself. 7File Size: 2MB.

    rotor finite-difference computations is the means of specifying vortices. The first finite- difference scheme to include vortices in the flow field [2] was for a potential solution to a high-tip-speed hover problem in which the vortices were specified as edges of potential discontinuities. This work had been preceded by extensive work in the finite difference modeling of turbine generators [37] [38]. The goal of this modeling was to predict the steady state operation of the generator such as the computation of excitation requirements under load and the computation of steady state : S. J. Salon.


Share this book
You might also like
Harness music to winds.

Harness music to winds.

Cotton weaving and designing.

Cotton weaving and designing.

Oranges and Lemons

Oranges and Lemons

Understanding statistics

Understanding statistics

Using WordStar 5

Using WordStar 5

Cultural policy.

Cultural policy.

Enemies of Leisure

Enemies of Leisure

Making the grade

Making the grade

Business ethics

Business ethics

Phase transformations

Phase transformations

Boston pilot

Boston pilot

Steel Allocation for Highways

Steel Allocation for Highways

Sri Ramakrishna

Sri Ramakrishna

Exploring Life Science Teachers Edition

Exploring Life Science Teachers Edition

Providing for the consideration of H.R. 1561, the Overseas Interests Act of 1995

Providing for the consideration of H.R. 1561, the Overseas Interests Act of 1995

Finite-difference computations of rotor loads Download PDF EPUB FB2

Future potential of finite-difference methods for solving real rotor problems which now rely largely on empiricism. The demonstration consists of a simple means of combining existing finite­ difference, integral, and comprehensive loads codes to predict real transonic rotor flows.

These computations are performed for hover and. The demonstration consists of a simple means of combining existing finite-difference, integral, and comprehensive loads codes to predict real transonic rotor flows. These computations are. COVID Resources.

Reliable information about the coronavirus (COVID) is available from the World Health Organization (current situation, international travel).Numerous and frequently-updated resource results are available from this ’s WebJunction has pulled together information and resources to assist library staff as they consider how to handle coronavirus.

Finite-difference computations of rotor loads. By C. Tung and F. Caradonna. Abstract. The current and future potential of finite difference methods for solving real rotor problems which now rely largely on empiricism are demonstrated. The demonstration consists of a simple means of combining existing finite-difference, integral, and Author: C.

Tung and F. Caradonna. Finite-difference computations of rotor loads. By C. Tung and F. Caradonna. Abstract. This paper demonstrates the current and future potential of finite-difference methods for solving real rotor problems which now rely largely on empiricism. The demonstration consists of a simple means of combining existing finite-difference, integral, and Author: C.

Tung and F. Caradonna. Finite Difference Modeling of Rotor Flows Including Wake Effects. However, practical rotor loads, finite difference computations have been made of hover flows using the relaxation. The rotor wake is a factor in almost all helicopter problems. A major issue in advanced aerodynamic methods is how the wake can be included.

Wake formation must at some level be considered a viscous phenomenon, and the helical geometry of the helicopter wake means that the detailed structure is important even at scales on the order of the rotor.

Good agreement is shown for the integral loads, radial distributions of blades forces, pressure distributions, and the velocity profiles up- and downstream of the rotor. AB - A comparison, between selected wind tunnel data from the NEW MEXICO measuring campaign and CFD computations.

The unsteady viscous flow around flat plates is investigated through a finite-difference computation of the incompressible two-dimensional Navier-Stokes equations. The side ratio of the plates d/h ranges from 3 to 10 with Reynolds numbers Re equal to andwhere d.

Numerical and Computer Methods in Structural Mechanics is a compendium of papers that deals with the numerical methods in structural mechanics, computer techniques, and computer capabilities. Some papers discus the analytical basis of the computer technique most widely used in software, that is, the finite element method.

The accurate prediction of rotor loads and vibration remains a difficult problem for helicopter design. Typically, helicopters encounter high vibration in two different speed regimes: transition and high speed. The rotor blade aerodynamic environment in transition File Size: KB.

Reducing the loads experienced by wind turbine rotor blades can lower the cost of energy of wind turbines. "Smart rotor control" concepts have emerged as a solution to reduce fatigue loads on wind. Download Zip Source Code. Here we exemplify how to expand Finite Difference (FD) computational kernels to run on distributed systems.

Additionally, we describe a technique that shows how to deal with the load imbalance of heterogeneous distributed systems where different nodes or compute devices may provide distinct compute speeds.

The object of this investigation was to find and demonstrate a means of performing efficient finite-difference computations of rotor loading for a trimmed rotor in high-speed, forward flight. We compare explicit finite difference solution for a European put with the exact Black-Scholes formula, where T = 5/12 yr, S 0=$50, K = $50, σ=30%, r = 10%.

Black-Scholes Price: $ as numerical computation progresses for fixed discretization steps and S. * i,j Size: KB. Fatigue load computation of wind turbine gearboxes by coupled finite element Article in Wind Energy 10(5) September with Reads How we measure 'reads'.

Rotor The rotor is the most expensive component of the flywheel system and all other components are designed to ease constraints on the rotor cheapest rotor design currently being tested, probably $40 per kWh, is the bare filament rotor approach conceived by Mr.

David Rabenhorst, of Johns Hopkins Applied Physics Laboratory. Journal of Sound and Vibration () 99(2), FINITE DIFFERENCE ANALYSIS OF TORSIONAL VIBRATIONS OF PRETWISTED, ROTATING, CANTILEVER BEAMS WITH EFFECTS OF WARPING K. SUBRAHMANYAMt AND K. KAZA National Aeronautics and Space Administration, Lewis Research Center, Structures Branch, Brookpark Road, Cleveland, OhioU.S.A.

Cited by: The finite element method (FEM), or finite element analysis (FEA), is a computational technique used to obtain approximate solutions of boundary value problems in engineering.

Boundary value problems are also called field problems. The field is the domain of interest File Size: 2MB. Review of Rotor Loads Prediction with the Emergence of Rotorcraft CFD Journal of the American Helicopter Society, Vol.

52, No. 4 30 Years of Rotorcraft Computational Fluid Cited by:. This book introduces the powerful Finite-Difference Time-Domain method to students and interested researchers and readers.

An effective introduction is accomplished using a step-by-step process that builds competence and confidence in developing complete working codes for the design and analysis of various antennas and microwave by: This book is a must for students in all fields of engineering, computational physics, scientific computing, and applied mathematics.

It can be used in both undergraduate and graduate courses in fluid mechanics, aerodynamics, and computational fluid by: Experimental studies of isolated rotors in forward flight have indicated considerable potential for noise reduction through the application of higher harmonic pitch control. Tests to date also show that such pitch inputs can also generate substantial vibratory loads.

This report summarizes the modification of the RotorCRAFT (Computation of Rotor.