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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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Programs based on equations that include functions for boundary values along nozzle axis yield different types of flow field configurations. Program's documentation details method of calculating subsonic flow field and sonic line, and describes modified method of characteristics for calculating supersonic flow downstream of sonic line.
Digital computer program computes and analyzes supersonic flow field in axisymmetric rocket nozzle for specified gas properties, nozzle geometry, and input or starting line. Method of characteristics is used for solution of set of hyperbolic partial differential equations.
Aerodynamic method of characteristics for pressure field calculations about wing-body combinations
Method of characteristics for calculating oblique shock wave interaction with turbulent boundary layer
Method of characteristics analytical technique for flow predictions of supersonic cross flows over conical bodies
Method of characteristics for determining cardiovascular parameters of flow pressure in arteries
Tuned resonant test for measuring damping characteristics of lead and asbestos filled epoxy- polysulfide copolymer
Three dimensional hypersonic steady flow around blunt and pointed cones at nonzero angles of attack calculated by method of characteristics
Nonuniform free stream supersonic flow past aerodynamic decelerators, calculating inviscid flow fields by method of characteristics
Analysis of supersonic and hypersonic flow of inviscid ideal gas over conical wings with sharp leading edges and attached shock waves by three dimensional method of characteristics
Hypersonic and supersonic angle of attack flow about asymmetric and axisymmetric blunt bodies based on time dependent finite difference theory and method of characteristics
Transform for hydrogen ion exchange perturbation problem, involving first order partial differential equations and method of characteristics
Fracture of bumper protected fuel tanks subjected to hypervelocity meteoroid impact, applying method of characteristics to stress wave propagation in tank walls
Plane normal shock wave reflection in relaxing gas for shock tube endwall upstream and downstream dynamic pressures, using method of characteristics
The method of characteristics for a chemically reacting gas is used in the construction of the time-dependent, one-dimensional flow field resulting from the normal reflection of an incident shock wave at the end wall of a shock tube. Nonequilibrium chemical reactions are allowed behind both the incident and reflected shock waves. All the solutions are evaluated for oxygen, but the results are generally representative of any inviscid, nonconducting, and nonradiating diatomic gas. The solutions clearly show that: (1) both the incident- and reflected-shock chemical relaxation times are important in governing the time to attain steady state thermodynamic properties; and (2) adjacent to the end wall, an excess-entropy layer develops wherein the steady state values of all the thermodynamic variables except pressure differ significantly from their corresponding Rankine-Hugoniot equilibrium values.
Fuel samples, 90UC - 10 ZrC, and chemically vapor deposited tungsten fuel cups were fabricated for the study of the long term dimensional stability and compatibility of the carbide-tungsten fuel-cladding systems under irradiation. These fuel samples and fuel cups were assembled into the fuel pins of two capsules, designated as V-2E and V-2F, for irradiation in NASA Plum Brook Reactor Facility at a fission power density of 172 watts/c.c. and a miximum cladding temperature of 1823 K. Fabrication methods and characteristics of the fuel samples and fuel cups prepared are described.
The transient response due to longitudinal impact of three aluminum cylindrical shells of different thickness-to-radius ratios is studied both analytically and experimentally. The analyses were obtained from method of characteristics' solutions of two sets of equations: one which includes the transverse shear, radial inertia, and rotary inertial effects; and the other set is from a modified membrane theory. Experimentally, longitudinal and circumferential strains are monitored along the length of each of the shells; the velocity of the impacter ring is also measured. The experimental results of this study indicate that the wave front, after traveling three diameters from the impacted end, propagates at essentially the plate velocity, in agreement with the theory. In addition, the longitudinal and circumferential strain calculated from the two theories are in good agreement with the experimental results.
The pressure, magnetic field, temperature, particle density, and stream velocity throughout the magnetosheath have been calculated in the plane containing the interplanetary field and solar wind velocity vector for various orientations of the interplanetary magnetic field and various assumed ratios of specific heats of the compressed solar wind. Jump conditions at the bow shock gave initial conditions in the shocked plasma from which the appropriate hydromagnetic equations (for blunt bodies in the subsonic region near the subsolar point and for the method of characteristics in the supersonic region back in the tail) were integrated numerically back to the surface of the magnetosphere. Explicit consideration of the magnetic field shows that a net asymmetrical force on the magnetopause produces a side force, or 'lift' in addition to the well-known drag on the magnetosphere.