Author: Karen A. DeerePublisher:
ISBN:
Category :
Languages : en
Pages : 54
Book Description
Experimental and Computational Investigation of a Translating-Throat Single-Expansion-Ramp Nozzle
Author: Karen A. DeereAn Experimental and Computational Investigation of a Translating Throat Single Expansion-ramp Nozzle
Author: Karen Ann DeereExperimental and Computational Investigation of a Translating-Throat Single-Expansion-Ramp Nozzle
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781720517351
Category :
Languages : en
Pages : 48
Book Description
An experimental and computational study was conducted on a high-speed, single-expansion-ramp nozzle (SERN) concept designed for efficient off-design performance. The translating-throat SERN concept adjusts the axial location of the throat to provide a variable expansion ratio and allow a more optimum jet exhaust expansion at various flight conditions in an effort to maximize nozzle performance. Three design points (throat locations) were investigated to simulate the operation of this concept at subsonic-transonic, low supersonic, and high supersonic flight conditions. The experimental study was conducted in the jet exit test facility at the Langley Research Center. Internal nozzle performance was obtained at nozzle pressure ratios (NPR's) up to 13 for six nozzles with design nozzle pressure ratios near 9, 42, and 102. Two expansion-ramp surfaces, one concave and one convex, were tested for each design point. Paint-oil flow and focusing schlieren flow visualization techniques were utilized to acquire additional flow data at selected NPR'S. The Navier-Stokes code, PAB3D, was used with a two-equation k-e turbulence model for the computational study. Nozzle performance characteristics were predicted at nozzle pressure ratios of 5, 9, and 13 for the concave ramp, low Mach number nozzle and at 10, 13, and 102 for the concave ramp, high Mach number nozzle.Deere, Karen A. and Asbury, Scott C.Langley Research CenterNAVIER-STOKES EQUATION; THROATS; EXHAUST NOZZLES; NOZZLE DESIGN; COMPUTATIONAL FLUID DYNAMICS; K-EPSILON TURBULENCE MODEL; NOZZLE EFFICIENCY; FLOW VISUALIZATION; TRANSONIC FLIGHT; SUPERSONIC FLIGHT; SCHLIEREN PHOTOGRAPHY
An Experiment and Computational Investigation of a Translating Throat Single Expansion-ramp Nozzle
Author: Karen A. DeereExperimental And Computational Investigation Of A Translating-Throat Single-Expansion-Ramp Nozzle... NASA/TP-1999-209138... August 6, 1999
Author: United States. National Aeronautics and Space AdministrationPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Nuits de Broadway (Broadway through a keyhole). Le film complet : ciné-roman
Author: Parametric Investigation of Single-expansion-ramp Nozzles at Mach Numbers from 0.60 to 1.20
Author: Francis J. CaponePublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 280
Book Description
Parametric Investigation of Single-Expansion-Ramp Nozzles at Mach Numbers from 0. 60 to 1. 20
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781724326720
Category :
Languages : en
Pages : 278
Book Description
An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of varying six nozzle geometric parameters on the internal and aeropropulsive performance characteristics of single-expansion-ramp nozzles. This investigation was conducted at Mach numbers from 0.60 to 1.20, nozzle pressure ratios from 1.5 to 12, and angles of attack of 0 deg +/- 6 deg. Maximum aeropropulsive performance at a particular Mach number was highly dependent on the operating nozzle pressure ratio. For example, as the nozzle upper ramp length or angle increased, some nozzles had higher performance at a Mach number of 0.90 because of the nozzle design pressure was the same as the operating pressure ratio. Thus, selection of the various nozzle geometric parameters should be based on the mission requirements of the aircraft. A combination of large upper ramp and large lower flap boattail angles produced greater nozzle drag coefficients at Mach number greater than 0.80, primarily from shock-induced separation on the lower flap of the nozzle. A static conditions, the convergent nozzle had high and nearly constant values of resultant thrust ratio over the entire range of nozzle pressure ratios tested. However, these nozzles had much lower aeropropulsive performance than the convergent-divergent nozzle at Mach number greater than 0.60. Capone, Francis J. and Re, Richard J. and Bare, E. Ann Langley Research Center NASA-TP-3240, L-17067, NAS 1.60:3240 RTOP 505-62-30-01...
Static Internal Performance of Convergent Single-Expansion-Ramp Nozzles with Various Combinations of Internal Geometric Parameters
Author: National Aeronautics and Space Adm NasaPublisher:
ISBN: 9781731033277
Category :
Languages : en
Pages : 106
Book Description
An investigation was conducted in the Static Test Facility of the Langley 16-Foot Transonic Tunnel to determine the effects of five geometric design parameters on the internal performance of convergent single expansion ramp nozzles. The effects of ramp chordal angle, initial ramp angle, flap angle, flap length, and ramp length were determined. All nozzles tested has a nominally constant throat area and aspect ratio. Static pressure distributions along the centerlines of the ramp and flap were also obtained for each configuration. Nozzle pressure ratio was varied up to 10.0 for all configurations. Bare, E. Ann and Capone, Francis J. Langley Research Center CONVERGENT NOZZLES; NOZZLE DESIGN; NOZZLE GEOMETRY; PRESSURE DISTRIBUTION; PRESSURE RATIO; WIND TUNNEL TESTS; ASPECT RATIO; DESIGN ANALYSIS; FLAPS (CONTROL SURFACES); RAMPS (STRUCTURES); STATIC PRESSURE; THROATS; TRANSONIC WIND TUNNELS...
Author: A. Dufour