Spreading of semi-confined jets
Effects of aspect ratio on spreading of semi-confined jets formed by round and sharp edged nozzle profiles
JET FLOW↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Two hundred sixty-in.-dia. motor program Final report
Normal motor and nozzle performance reported for static test firing of 44-SS-4 motor
NOZZLE GEOMETRY↗
A general method for determining optimum thrust nozzle contours for chemically reacting gas flows.
Optimum thrust nozzle contours for chemically reacting gas flows, obtaining set of partial differential equations for gas dynamic properties
SUPERSONIC NOZZLE↗
Status of the 260-inch diameter solid rocket motor program.
Third 260-inch diameter solid propellant rocket engine test firing
NOZZLE GEOMETRY↗
Selection of nozzle contours for a research scramjet engine.
Scramjet engine nozzle contours noting expansion- deflection, bell, plug and arbitrary annular nozzles, with optimum nozzle design and computer program for performance prediction
NOZZLE GEOMETRY↗
Optimum thrust-nozzle contours for gas-particle flows.
Optimization analysis for axisymmetric rocket motor nozzle design based on assumptions for gas particle flow
DIFFERENTIAL EQUATION↗
Bell nozzle kernel analysis program
Bell Nozzle Kernel Analysis Program computes and analyzes the supersonic flowfield in the kernel, or initial expansion region, of a bell or conical nozzle. It analyzes both plane and axisymmetric geometrices for specified gas properties, nozzle throat geometry and input line.
Elliot, J. J.↗
Solid motor aft closure insulation erosion
The erosion rate of aft closure insulation in a number of large solid propellant motors was empirically analyzed by correlating the average ablation rate with a number of variables that had previously been demonstrated to affect heat flux. The main correlating parameter was a heat flux based on the simplified Bartz heat transfer coefficient corrected for two-dimensional effects. A multiplying group contained terms related to port-to-throat ratio, local wall angle, grain geometry and nozzle cant angle. The resulting equation gave a good correlation and is a useful design tool.
Stampfl, E.↗
A summary of experimental research on propulsive-lift concepts in the Langley 16-foot transonic tunnel
A summary of research on both conceptual and practical configurations in which the aircraft's powerplant is integrated to take advantage of propulsion-induced aerodynamics conducted in the Langley 16-foot transonic tunnel has been made. These investigations included: (1) vectoring a partial-span jet exhaust at a wing trailing edge; (2) thrust vectoring characteristics of a twin, two-dimensional variable-geometry wedge nozzle; (3) a jet exhaust/upper surface blowing concept for fighter aircraft; and (4) jets blowing over the wing. These studies indicate a potential for increasing maneuverability of fighter aircraft at high lift coefficients. With proper integration of the powerplant and the airframe, significant improvements in cruise performance of both fighter and transport aircraft are possible.
Capone, F. J.↗
Problems in propulsion system integration
Jet engine components are considered that influence propulsion system integration on the airframe and related aircraft drag areas. Emphasis is placed on high Mach number inlet geometries, boattailed nozzle configurations, propulsive wing installation, wing surface blowing lift, fuselage mounted nacelles, and thrust reversal.
Henderson, W. P.↗
Two dimensional wedge/translating shroud nozzle
A jet propulsion exhaust nozzle is reported for multi-engine installations which produces high internal/external, thrust-minus-drag, performance for transonic cruise or transonic acceleration as well as improved performance at subsonic and supersonic speeds. A two dimensional wedge/translating shroud provides the variable nozzle exit geometry needed to achieve high engine performance over a wide range of throttle power settings.
Maiden, D. L.↗
A wind tunnel application of large-field focusing schlieren
A large-field focusing schlieren apparatus was installed in the NASA Lewis Research Center 9 by 15 foot wind tunnel in an attempt to determine the density gradient flow field of a free jet issuing from a supersonic nozzle configuration. The nozzle exit geometry was designed to reduce acoustic emissions from the jet by enhancing plume mixing. Thus, the flow exhibited a complex three-dimensional structure which warranted utilizing the sharp focusing capability of this type of schlieren method. Design considerations concerning tunnel limitations, high-speed photography, and video tape recording are presented in the paper.
Ponton, Michael K.↗
Numerical simulation of jet aerodynamics using the three-dimensional Navier-Stokes code PAB3D
This report presents a unified method for subsonic and supersonic jet analysis using the three-dimensional Navier-Stokes code PAB3D. The Navier-Stokes code was used to obtain solutions for axisymmetric jets with on-design operating conditions at Mach numbers ranging from 0.6 to 3.0, supersonic jets containing weak shocks and Mach disks, and supersonic jets with nonaxisymmetric nozzle exit geometries. This report discusses computational methods, code implementation, computed results, and comparisons with available experimental data. Very good agreement is shown between the numerical solutions and available experimental data over a wide range of operating conditions. The Navier-Stokes method using the standard Jones-Launder two-equation kappa-epsilon turbulence model can accurately predict jet flow, and such predictions are made without any modification to the published constants for the turbulence model.
Pao, S. Paul↗
Afterbody External Aerodynamic and Performance Prediction at High Reynolds Numbers
This CFD experiment concludes that the potential difference between the flow between a flight Reynolds number test and a sub-scale wind tunnel test are substantial for this particular nozzle boattail geometry. The early study was performed using a linear k-epsilon turbulence model. The present study was performed using the Girimaji formulation of a algebraic Reynolds stress turbulent simulation.
Carlson, John R.↗
Summary of Fluidic Thrust Vectoring Research Conducted at NASA Langley Research Center
Interest in low-observable aircraft and in lowering an aircraft's exhaust system weight sparked decades of research for fixed geometry exhaust nozzles. The desire for such integrated exhaust nozzles was the catalyst for new fluidic control techniques; including throat area control, expansion control, and thrust-vector angle control. This paper summarizes a variety of fluidic thrust vectoring concepts that have been tested both experimentally and computationally at NASA Langley Research Center. The nozzle concepts are divided into three categories according to the method used for fluidic thrust vectoring: the shock vector control method, the throat shifting method, and the counterflow method. This paper explains the thrust vectoring mechanism for each fluidic method, provides examples of configurations tested for each method, and discusses the advantages and disadvantages of each method.
Deere, Karen A.↗
Simulation of Cold Flow in a Truncated Ideal Nozzle with Film Cooling
Flow transients during rocket start-up and shut-down can lead to significant side loads on rocket nozzles. The capability to estimate these side loads computationally can streamline the nozzle design process. Towards this goal, the flow in a truncated ideal contour (TIC) nozzle has been simulated for a range of nozzle pressure ratios (NPRs) aimed to match a series of cold flow experiments performed at the NASA MSFC Nozzle Test Facility. These simulations were performed with varying turbulence model choices and with four different versions of the TIC nozzle model geometry, each of which was created with a different simplification to the test article geometry.
Braman, Kalen↗
Geometric Sensitivity of Residual Fields in Metal Additive Manufacturing
The sensitivity of geometrical parameters on the residual stress and distortion as computed by a metal additive manufacturing simulation is presented. A nozzle-like geometry was chosen with its length, wall thickness, and outer radius varied. A Latin hypercube sampling of 300 specimens produced the combinations of the geometrical parameters. Full thermomechanical simulations predicted the residual fields. Statistical analysis including regression curves shows that there is a strong correlation between these residual fields and the geometry, hinting that it may be possible to predictably influence the residual displacements and residual stresses by varying the overall geometry.
Multiscale Modeling↗
Rapid Prediction of Unsteady Three-Dimensional Viscous Flows in Turbopump Geometries
A program is underway to improve the efficiency of a three-dimensional Navier-Stokes code and generalize it for nozzle and turbopump geometries. Code modifications have included the implementation of parallel processing software, incorporation of new physical models and generalization of the multiblock capability. The final report contains details of code modifications, numerical results for several nozzle and turbopump geometries, and the implementation of the parallelization software.
Dorney, Daniel J.↗