Download or read book NEAR FIELD SCREECH NOISE COMPUTATION FOR AN UNDEREXPANDED SUPERSONIC JET BY THE CE SE METHOD NASA TM 2001 210958 DEC 6 2001 written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near Field Screech Noise Computation for an Underexpanded Supersonic Jet by the CE SE Method written by and published by . This book was released on 2001 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near field Screen Noise Computation for an Under expanded Supersonic Jet by the CE SE Method written by Ching Y. Loh and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near Field Screech Noise Computation for An Underexpanded Supersonic Jet By the Ce written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Jet Screech Noise Computation written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-20 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The near-field screech-tone noise of a typical underexpanded circular jet issuing from a sonic nozzle is simulated numerically. The self-sustained feedback loop is automatically established in the simulation. The computed shock-cell structure, acoustic wave length, screech tone frequencies, and sound pressure levels in the near field are in good agreement with existing experimental results. Loh, Ching Y. and Hultgren, Lennart S. Glenn Research Center NASA/TM-2003-212626, E-14184, NAS 1.15:212626
Download or read book Computation of Tone Noise from Supersonic Jet Impinging on Flat Plates written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A supersonic jet impinging normally on a flat plate has both practical importance and theoretical interests. The physical phenomenon is not fully understood yet. Research concentrates either on the hydrodynamics (e.g., lift loss for STOVL) or on the aeroacoustic loading. In this paper, a finite volume scheme - the space-time conservation element and solution element (CE/SE) method - is employed to numerically study the near-field noise of an underexpanded supersonic jet from a converging nozzle impinging normally on a flat plate. The numerical approach is of the MILES type (monotonically integrated large eddy simulation). The computed results compare favorably with the experimental findings. Loh, Ching Y. and Blech, Richard A. (Technical Monitor) Glenn Research Center NASA/CR?2005-213426, AIAA Paper 2005?0418, E?14959
Download or read book SIMULATION OF SUPERSONIC JET NOISE WITH THE ADAPTATION OF OVERFLOW CFD CODE AND KIRCHHOFF SURFACE INTEGRAL NASA TM 2001 210263 DEC 6 written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computing Jet Screech A Complex Aeroacoustic Feedback System written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-27 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The space-time conservation-element and solution-element method is employed to numerically study the near-field axisymmetric screech-tone noise of a typical underexpanded circular jet issuing from a sonic nozzle. For the computed case, corresponding to a fully expanded Mach number of 1.19, the self-sustained feedback loop is established without artificial means. The computed shock-cell structure, acoustic wave length, screech tone frequency, and sound pressure levels are in good agreement with existing experimental results Loh, Ching Y. and Hultgren, Lennart S. Glenn Research Center NASA/TM-2002-211807, E-13502, NAS 1.15:211807
Download or read book Simulation of Supersonic Jet Noise with the Adaptation of Overflow Cfd Code and Kirchhoff Surface Integral written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: An acoustic prediction capability for supersonic axisymmetric jets was developed on the basis of OVERFLOW Navier-Stokes CFD (Computational Fluid Dynamics) code of NASA Langley Research Center. Reynolds-averaged turbulent stresses in the flow field are modeled with the aid of Spalart-Allmaras one-equation turbulence model. Appropriate acoustic and outflow boundary conditions were implemented to compute time-dependent acoustic pressure in the nonlinear source-field. Based on the specification of acoustic pressure, its temporal and normal derivatives on the Kirchhoff surface, the near-field and the far-field sound pressure levels are computed via Kirchhoff surface integral, with the Kirchhoff surface chosen to enclose the nonlinear sound source region described by the CFD code. The methods are validated by a comparison of the predictions of sound pressure levels with the available data for an axisymmetric turbulent supersonic (Mach 2) perfectly expanded jet. Kandula, Max and Caimi, Raoul and Steinrock, T. (Technical Monitor) Kennedy Space Center NASA/TM-2001-210263, NAS 1.15:210263
Download or read book Gap Noise Computation by the Ce written by United States. National Aeronautics and Space Administration and published by . This book was released on 2003* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near Field and Far Field Noise Measurements for a Blowdown Wind Tunnel Supersonic Exhaust Jet Having about 475 000 Pounds of Thrust written by William H. Mayes and published by . This book was released on 1961 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Near-field and far-field noise surveys were made of the supersonic The exhaust jet of the Langley 9- by 6-foot thermal structures tunnel. The jet had a thrust rating of approximately 475,000 pounds. The sound power radiated was found to be about 3.6 x 10(exp 6) watts, and on an acoustical-mechanical efficiency basis this value is in reasonable agreement with data for smaller supersonic jets and for rocket engines of other investigations. Octave-band analyses of the near-field noise show that the maximum sound pressure levels in the low-frequency bands are greatest downstream, whereas maximum sound pressure levels in the high-frequency bands were greatest near the jet exit. A comparison of near-field noise measurements is made with data previously obtained for rocket engines. Noise survey measurements of the original jet are compared with similar data obtained after the addition of a 97-foot-long exit diffuser section, and an example of the application of this facility to the problem of acoustic environmental testing of a large space capsule is cited.
Download or read book On the Prediction of the Near Field Noise of Supersonic Jets written by J. B. Ollerhead and published by . This book was released on 1967 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Subsonic and Supersonic Jet Noise Calculations Using PSE and DNS written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-11 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise radiated from a supersonic jet is computed using the Parabolized Stability Equations (PSE) method. The evolution of the instability waves inside the jet is computed using the PSE method and the noise radiated to the far field from these waves is calculated by solving the wave equation using the Fourier transform method. We performed the computations for a cold supersonic jet of Mach number 2.1 which is excited by disturbances with Strouhal numbers St=.2 and .4 and the azimuthal wavenumber m=l. Good agreement in the sound pressure level are observed between the computed and the measured (Troutt and McLaughlin 1980) results.Balakumar, P. and Owis, FaroukLangley Research CenterJET AIRCRAFT NOISE; SUPERSONIC JET FLOW; SUBSONIC FLOW; STABILITY; FAR FIELDS; WAVE EQUATIONS; FOURIER TRANSFORMATION; SOUND PRESSURE; COLD GAS; STROUHAL NUMBER; AZIMUTH
Download or read book Near Field Trailing Edge Tone Noise Computation written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-20 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Blunt trailing edges in a flow often generate tone noise due to wall-jet shear layer and vortex shedding. In this paper, the space-time conservation element (CE/SE) method is employed to numerically study the near-field noise of blunt trailing edges. Two typical cases, namely, flow past a circular cylinder (aeolian noise problem) and flow past a flat plate of finite thickness are considered. The computed frequencies compare well with experimental data. For the aeolian noise problem, comparisons with the results of other numerical approaches are also presented. Loh, Ching Y. Glenn Research Center NASA/CR-2002-212013, NAS 1.26:212013, E-13703, AIAA Paper 2003-0365
Download or read book Noise Computation of a Shock containing Supersonic Axisymmetric Jet by the CE SE Method written by Ching Yuen Loh and published by . This book was released on 1999 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near field Noise Computation for a Supersonic Circular Jet written by Ching Yuen Loh and published by . This book was released on 2005 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Near Field Trailing Edge Tone Noise Computation written by Ching Y. Loh and published by . This book was released on 2002 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
