Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies. Part I. Detailed Surface Measurements

Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies. Part I. Detailed Surface Measurements
Author: John A. Benek
Publisher:
Total Pages: 52
Release: 1979
Genre:
ISBN:

Extensive static pressure data were obtained on a model consisting of a cone-ogive-cylinder forebody, two interchangeable circular arc afterbody boattails having length-to-forebody diameter ratios of 0.80 and 1.77, and two interchangeable solid exhaust plume simulators of cylindrical and contoured geometry. Boundary-layer pitot data and photographic records of model tufts and schlieren data were also obtained. Data were collected over a Mach number range of 0.60 to 1.30 and a unit Reynolds number range of 3.2 to 13.12 million per m (1 to 4 million per ft) at zero angle of attack and sideslip for the purpose of obtaining experimental data suitable for comparison with theoretical predictions. Data are presented for two model configurations with cylindrical solid plume simulators at three flow conditions: (1) length-to-diameter ratio = 1.77 boattail at Mach number number 0.80 and Reynolds number 8.2 million per m for high subsonic, unseparated flow; (2) length-to-diameter ratio = 0.80 boattail at Mach number 0.60 and unit Reynolds number 8.2 million per m for subsonic, separated flow; and (3) length-to-diameter ratio = 0.80 boattail at Mach number 0.95 and unit Reynolds number 8.2 million per m for transonic, separated flow with boundary-layer-shock interaction. (Author).

Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies

Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies
Author: John A. Benek
Publisher:
Total Pages: 54
Release: 1979
Genre: Exhaust nozzles
ISBN:

Extensive static pressure data were obtained on a model consisting of a cone-ogive-cylinder forebody, two interchangeable circular arc afterbody boattails having length-to-forebody diameter ratios of 0.80 and 1.77, and two interchangeable solid exhaust plume simulators of cylindrical and contoured geometry. Boundary-layer pitot data and photographic records of model tufts and schlieren data were also obtained. Data were collected over a Mach number range of 0.60 to 1.30 and a unit Reynolds number range of 3.2 to 13.12 million per m (1 to 4 million per ft) at zero angle of attack and sideslip for the purpose of obtaining experimental data suitable for comparison with theoretical predictions. Data are presented for two model configurations with cylindrical solid plume simulators at three flow conditions: (1) length-to-diameter ratio = 1.77 boattail at Mach number number 0.80 and Reynolds number 8.2 million per m for high subsonic, unseparated flow; (2) length-to-diameter ratio = 0.80 boattail at Mach number 0.60 and unit Reynolds number 8.2 million per m for subsonic, separated flow; and (3) length-to-diameter ratio = 0.80 boattail at Mach number 0.95 and unit Reynolds number 8.2 million per m for transonic, separated flow with boundary-layer-shock interaction. (Author).

Computation of Axisymmetric Separated Nozzle-afterbody Flow

Computation of Axisymmetric Separated Nozzle-afterbody Flow
Author: James L. Jacocks
Publisher:
Total Pages: 36
Release: 1980
Genre: Airplanes
ISBN:

The development of a computer program for solving the compressible, axisymmetric, mass-averaged Navier-Stokes equations is described. The basic numerical algorithm is the MacCormack explicit predictor-corrector scheme. Turbulence modeling is accomplished using an algebraic, two-layer eddy viscosity model with a novel modification dependent on the streamwise gradient of vorticity. Comparisons of computed results with experimental data are presented for several nozzle-afterbody configurations with either or simulated plumes. (Author).

Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies. Part II. Detailed Flow Measurements

Separated and Nonseparated Turbulent Flows about Axisymmetric Nozzle Afterbodies. Part II. Detailed Flow Measurements
Author: John A. Benek
Publisher:
Total Pages: 216
Release: 1979
Genre:
ISBN:

Measurements of mean velocity, specific turbulent kinetic energy, and specific Reynolds shear were obtained at M to the base infinity = 0.64 and ReD = 288,600 in a symmetry plane of two axisymmetric, circular-arc, boattail geometries each of which had a solid plume simulator. The geometries were selected such that an attached- and a separated flow boundary layer would be obtained. Ancillary measurements, consisting of model surface and tunnel wall, axial, static pressure distributions, and velocity vectors near the tunnel wall provide a well-defined domain with which to validate numerical flow simulations. Tabulations of the data and coefficients of least-squares dubic spline fits to the data are presented. (Author).

Two-component Simultaneous LDV Turbulence Measurements in an Axisymmetric Nozzle Afterbody Subsonic Flow Field with a Cold, Underexpanded Supersonic Jet

Two-component Simultaneous LDV Turbulence Measurements in an Axisymmetric Nozzle Afterbody Subsonic Flow Field with a Cold, Underexpanded Supersonic Jet
Author: F. L. Heltsley
Publisher:
Total Pages: 250
Release: 1983
Genre: Airplanes
ISBN:

A test was conducted to obtain nonintrusive measurements in the flow field about an axisymmetric nozzle afterbody with a cold, underexpanded jet, M sub j=1.563, in a parallel free stream, M sub alpha = 0.6. Reynolds shear stress and two components of mean velocity and turbulence intensity were measured using a two-color Bragg-diffracted laser Doppler velocimeter. Additional experimental data include the afterbody surface pressure distribution and laser vapor screen flow visualization of the jet plume. A multiple seeding technique was used to investigate the bimodal velocity probability distributions observed in the jet mixing region. (Author).

Physics of Separated Flows — Numerical, Experimental, and Theoretical Aspects

Physics of Separated Flows — Numerical, Experimental, and Theoretical Aspects
Author: Klaus Gersten
Publisher: Springer Science & Business Media
Total Pages: 305
Release: 2013-06-29
Genre: Science
ISBN: 3663139867

This volume contains 37 contributions in which the research work is summarized which has been carried out between 1984 and 1990 in the Priority Research Program "Physik abgeloster Stromungen" of the Deutsche Forschungsgemeinschaft (DFG, German Research Society). The aim of the Priority Research Program was the inten sive research of the whole range of phenomena associated with separated flows. Physi cal models as well as prediction methods had to be developed based on detailed experi mental investigations. It was in accordance with the main concept of the research program that scientists working on problems of separated flows in different technical areas of application participated in this program. The following fields have been represented in the program: aerodynamics of wings and bodies, aerodynamics of auto mobiles, turbomachinery, ship hydrodynamics, hydraulics, internal flows, heat exchan gers, bio-fluid-dynamics, aerodynamics of buildings and structures. In order to concentrate on problems common in all those areas the emphasis of the program was on basic research dealing with generic geometric configurations showing the fundamental physical phenomena of separated flows. The engagement and enthusiasm of all participating scientists are highly appreciated. The program was organized such that all researchers met once a year to report on the progress of their work. Special thanks ought to go to Prof. E. A. Muller (Gottingen), Prof. H. Oertel jun. (Braunschweig), Dr. W. Schmidt (Dornier), Dr. H. -W. Stock (Dornier) and Dr. B. Wagner (Dornier), who had the functions of referees on those annual meetings.