Download or read book Noise Suppression in Jet Inlets written by Ben T. Zinn and published by . This book was released on 1978 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the work performed during the second year of an AFOSR sponsored research program that was primarily concerned with the development of an analytical technique for determining the radiated sound field from axisymmetric jet engine inlet configurations. The analytical technique employed is based upon an integral representation of the external (radiation) solutions of the Helmholtz equation which describe the sound fields external to a given body under either no flow or constant velocity flow situations. The integral representation developed during the course of this research program is different from earlier works in the sense that it not only yields the correct (unique) solution for all radiation problems at all frequencies, but that the resulting integral equations contain no strong (i.e., nonintegrable) singularities and therefore can be solved by straight forward numerical techniques.
Download or read book Noise Suppression in Jet Inlets written by Ben T. Zinn and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sound Measurements on a Full scale Jet engine Inlet noise suppressor Cowling written by L. Jack Smith and published by . This book was released on 1968 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inlet Noise Suppressor Performance with a Turbojet Engine as the Noise Source written by John Frederick Groeneweg and published by . This book was released on 1971 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inlet noise suppressors having perforated plate over honeycomb wall construction evaluated over range of passage heights and engine speeds using turbojet engine as noise source.
Download or read book Fundamental Study of Jet Noise Generation and Suppression written by W. C. Sperry and published by . This book was released on 1961 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Survey of Inlet Noise Reduction Concepts for Gas Turbine Engines written by and published by . This book was released on 1976 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alleviation of Jet Aircraft Noise Near Airports written by Jet Aircraft Noise Panel (U.S.) and published by . This book was released on 1966 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supersonic Transport Noise Reduction Technology Program Phase II written by S. B. Kazin and published by . This book was released on 1975 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Supersonic Transport Noise Reduction Technology Program, sponsored by the Federal Aviation Administration, was conducted as a follow-on effort after cancellation of the SST Program to finalize selected noise technology areas and summarize results of the SST Program. Using initial effects of the SST Program, as summarized in Phase I of The Supersonic Transport Noise Reduction Technology Program, the Phase II contract was issued to the General Electric Company (and Boeing) to continue this important work. The overall program objective was to provide additional acoustic technology necessary, to design high speed aircraft systems, recognizing future acceptable noise levels. General Electric's effort was divided into the acoustic technology areas of jet noise reduction, turbomachinery noise reduction, and aircraft system integration. Jet noise reduction technology work was achieved through analytical studies, model tests, and J79 engine tests. Selected suppression systems identified during the SST Program were further refined (multispoke/chute suppressors or annular plug nozzles). Novel advanced concepts of suppression were identified, and extensive aerodynamic (static and wind-on) performance tests and hot-jet acoustic tests were performed.
Download or read book Investigation of Coaxial Jet Noise and Inlet Choking Using an F 111A Airplane written by Terrill W. Putnam and published by . This book was released on 1973 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of engine noise generated by an F-111A airplane positioned on a thrustmeasuring platform were made at angles of 0 deg to 160 deg from the aircraft heading. Sound power levels, power spectra, and directivity patterns are presented for jet exit velocities between 260 feet per second and 2400 feet per second. The test results indicate that the total acoustic power was proportional to the eighth power of the core jet velocity for core exhaust velocities greater than 300 meters per second (985 feet per second) and that little or no mixing of the core and fan streams occurred. The maximum sideline noise was most accurately predicted by using the average jet velocity for velocities above 300 meters per second (985 feet per second). The acoustic power spectrum was essentially the same for the single jet flow of afterburner operation and the coaxial flow of the nonafterburning condition. By varying the inlet geometry and cowl position, reductions in the sound pressure level of the blade passing frequency on the order of 15 decibels to 25 decibels were observed for inlet Mach numbers of 0.8 to 0.9.
Download or read book Noise Suppression with High Mach Number Inlets written by Edward Lumsdaine and published by . This book was released on 1976 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hybrid Active Passive Jet Engine Noise Suppression System written by and published by . This book was released on 1999 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Noise Suppression by an Acoustically Treated Three ring Inlet on a TF 34 Engine written by Gene Logan Minner and published by . This book was released on 1976 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alleviation of Jet Aircraft Noise Near Airports written by United States. Office of Science and Technology and published by . This book was released on 1966 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inlet Noise Suppressor Performance with a Turbojet Engine as the Noise Source written by John Frederick Groeneweg and published by . This book was released on 1971 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbojet Engine Noise Reduction with Mixing Nozzle ejector Combinations written by Willard D. Coles and published by . This book was released on 1958 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several noise suppressors consisting of combinations of mixing nozzles and ejectors were tested on two full-scale turbojet engines. Maximum sound pressure level reductions of 12 decibels and sound power level reductions of 8 decibels were obtained. The ejectors provided 3 to 5 decibels of the sound power reduction. The effects of ejector dimensions on noise suppression and engine performance were investigated. Ejector lengths of approximately 2.0 standard nozzle diameters and ejector diameters larger than 1.6 standard nozzle diameters provided the greatest additional noise reduction to that obtained with the mixing nozzles alone. The ejector can restore the static thrust loss caused by use of the mixing nozzle or can provide static-thrust augmentation.
Download or read book Jet Noise Suppressor Nozzle Development for Augmentor Wing Jet STOL Research Aircraft C 8A Buffalo written by D. L. Harkonen and published by . This book was released on 1974 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbojet engine Noise Studies to Evaluate Effects of Inlet guide vane rotor Spacing written by John L. Crigler and published by . This book was released on 1968 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
