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Book Prediction Techniques for Jet Induced Effects in Hover on Stovl Aircraft

Download or read book Prediction Techniques for Jet Induced Effects in Hover on Stovl Aircraft written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-10-18 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Prediction techniques for jet induced lift effects during hover are available, relatively easy to use, and produce adequate results for preliminary design work. Although deficiencies of the current method were found, it is still currently the best way to estimate jet induced lift effects short of using computational fluid dynamics. Its use is summarized. The new summarized method, represents the first step toward the use of surface pressure data in an empirical method, as opposed to just balance data in the current method, for calculating jet induced effects. Although the new method is currently limited to flat plate configurations having two circular jets of equal thrust, it has the potential of more accurately predicting jet induced effects including a means for estimating the pitching moment in hover. As this method was developed from a very limited amount of data, broader applications of the method require the inclusion of new data on additional configurations. However, within this small data base, the new method does a better job in predicting jet induced effects in hover than the current method. Wardwell, Douglas A. and Kuhn, Richard E. Ames Research Center RTOP 505-68-71...

Book Jet Induced Ground Effects on a Parametric Flat Plate Model in Hover

Download or read book Jet Induced Ground Effects on a Parametric Flat Plate Model in Hover written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-25 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The jet-induced forces generated on short takeoff and vertical landing (STOVL) aircraft when in close proximity to the ground can have a significant effect on aircraft performance. Therefore, accurate predictions of these aerodynamic characteristics are highly desirable. Empirical procedures for estimating jet-induced forces during the vertical/short takeoff and landing (V/STOL) portions of the flight envelope are currently limited in accuracy. The jet-induced force data presented significantly add to the current STOVL configurations data base. Further development of empirical prediction methods for jet-induced forces, to provide more configuration diversity and improved overall accuracy, depends on the viability of this STOVL data base. The data base may also be used to validate computational fluid dynamics (CFD) analysis codes. The hover data obtained at the NASA Ames Jet Calibration and Hover Test (JCAHT) facility for a parametric flat-plate model is presented. The model tested was designed to allow variations in the planform aspect ratio, number of jets, nozzle shape, and jet location. There were 31 different planform/nozzle configurations tested. Each configuration had numerous pressure taps installed to measure the pressures on the undersurface of the model. All pressure data along with the balance jet-induced lift and pitching-moment increments are tabulated. For selected runs, pressure data are presented in the form of contour plots that show lines of constant pressure coefficient on the model undersurface. Nozzle-thrust calibrations and jet flow-pressure survey information are also provided. Wardwell, Douglas A. and Hange, Craig E. and Kuhn, Richard E. and Stewart, Vearl R. Ames Research Center NASA-TM-104001, A-93040, NAS 1.15:104001 RTOP 505-68-32...

Book Jet induced Effects

Download or read book Jet induced Effects written by Richard E. Kuhn and published by AIAA (American Institute of Aeronautics & Astronautics). This book was released on 2006 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique characteristics of V/STOL flight bring with it unique aerodynamic challenges. Intended for the working professional or those in engineering graduate programs involved with V/STOL, this book provides information on the aerodynamic effects induced by the exiting flows of jet and fan powered V/STOL aircraft in hover and transition flight.

Book Multi Jet Induced Forces and Moments on VTOL Aircraft Hovering in and Out of Ground Effect

Download or read book Multi Jet Induced Forces and Moments on VTOL Aircraft Hovering in and Out of Ground Effect written by Donald R. Kotansky and published by . This book was released on 1977 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: An engineering methodology has been developed for the prediction of propulsive lift system induced aerodynamic effects for multi-lift-jet VTOL aircraft operating in the hover mode in an out of ground effect. The developed methodology takes into account the effects of aircraft geometry, aircraft orientation (pitch, roll) and height above the ground plane, cross-flow, lift- jet vector directions with respect to the airframe, lift-jet exit flow conditions and noncircular nozzle exit geometry for low aspect ratio nozzles.

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Monthly Catalogue  United States Public Documents

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1992 with total page 982 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book On the Estimation of Jet Induced Fountain Lift and Additional Suckdown in Hover for Two Jet Configurations

Download or read book On the Estimation of Jet Induced Fountain Lift and Additional Suckdown in Hover for Two Jet Configurations written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-10-29 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently available methods for estimating the net suckdown induced on jet V/STOL aircraft hovering in ground effect are based on a correlation of available force data and are, therefore, limited to configurations similar to those in the data base. Experience with some of these configurations has shown that both the fountain lift and additional suckdown are overestimated but these effects cancel each other for configurations within the data base. For other configurations, these effects may not cancel and the net suckdown could be grossly overestimated or underestimated. Also, present methods do not include the prediction of the pitching moments associated with the suckdown induced in ground effect. An attempt to develop a more logically based method for estimating the fountain lift and suckdown based on the jet-induced pressures is initiated. The analysis is based primarily on the data from a related family of three two-jet configurations (all using the same jet spacing) and limited data from two other two-jet configurations. The current status of the method, which includes expressions for estimating the maximum pressure induced in the fountain regions, and the sizes of the fountain and suckdown regions is presented. Correlating factors are developed to be used with these areas and pressures to estimate the fountain lift, the suckdown, and the related pitching moment increments. Kuhn, Richard E. and Bellavia, David C. and Corsiglia, Victor R. and Wardwell, Douglas A. Ames Research Center...

Book Lift and Pitching Moment Induced on Jet STOVL Aircraft Hovering in Ground Effect

Download or read book Lift and Pitching Moment Induced on Jet STOVL Aircraft Hovering in Ground Effect written by Richard E. Kuhn and published by . This book was released on 1993 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: The data obtained during an investigation of the effects of crossflow on the suckdown and fountain effects induced by various arrangements of vertically impinging jets are presented in this report. The jet arrangements included circular and rectangular jets in various single, dual and triple jet configurations. The tests were conducted in the 14 by 22 foot tunnel at the NASA Langley Research Center. Tests covered a range of heights above the ground, nozzle pressure ratios, and forward velocities.

Book Aeronautical Engineering

Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book NASA SP

    Book Details:
  • Author :
  • Publisher :
  • Release : 1992
  • ISBN :
  • Pages : 654 pages

Download or read book NASA SP written by and published by . This book was released on 1992 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book An Empirical Method for Estimating the Effect of Ground Proximity on the Jet induced Lift of VSTOL Aircraft Employing Rectangular Jets

Download or read book An Empirical Method for Estimating the Effect of Ground Proximity on the Jet induced Lift of VSTOL Aircraft Employing Rectangular Jets written by J. A. Sansone and published by . This book was released on 1981 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: