SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 43, ISSUE 25 - DECEMBER 16, 2005

02 AERODYNAMICS
Includes aerodynamics of flight vehicles, test bodies, airframe components and combinations, wings, and control surfaces.

Also includes aerodynamics of rotors, stators, fans, and other elements of turbomachinery.

For related information see also 34 Fluid Mechanics and Thermodynamics.

20050240987 Lawrence Livermore National Lab., Livermore, CA USA

Ultra-High Pressure Modeling and Experiments Review

Costantino, M.; Darnell, I.; Jun. 03, 2004; 14 pp.; In English Report No.(s): DE2005-15014206; UCRL-CONF-204471; No Copyright; Avail.: Department of Energy Information Bridge

The RDHWT/MARIAH II energy addition, run time, and mass flow rate requirements imply large air and nitrogen fluid volumes at the highest practicable static enthalpy. The objective of the gas supply concept development is the satisfaction of ultra-high pressure (UHP), high temperature thermodynamic requirements in a facility with acceptable safety and economic risks. The primary challenges for the mechanical design are connecting multiple volumes at pressures greater than 1,400MPa and temperatures greater than 500 K; fabricating high strength steel sections approximately 2 m in typical dimension, and reacting the pressure-related forces in the system. In the 'octahedral module' concept, four UHP intensifiers and two UHP manifolds are arranged in an 'octahedral' geometry that results in acceptable deviatoric stresses at cross bores. Multiple modules join to provide the required UHP volume at a stagnation pressure of 2100MPa and stagnation temperature of 750 K. NTIS

Stagnation Pressure; Modules; Stagnation Temperature; Fabrication

20050241674 Civil Aerospace Medical Inst., Oklahoma City, OK, USA

Fatality and Injury Rates for Two Types of Rotorcraft Accidents

Palmerron, David; October 2005; 9 pp.; In English Report No.(s): DOT/FAA/AM-05/17; No Copyright; Avail.: CASI: A02, Hardcopy

An analysis of the frequency of four different types of rotorcraft accidents was conducted to determine if the number of fatalities and injuries between accident conditions was different. Accidents involving rollover, no rollover, fire, and no fire were studied to determine if accidents with a rollover or fire might be creating evacuation delays that contribute to the fatality and injury rates. A search of the FAA Accident Incident Data Systems from January 1986 to March 1997 produced 2704 accident records for this analysis. A Chi-Square test for independence was used to determine the difference between the rollover and no rollover and fire and no fire accident categories. Further analysis were performed on combinations of the main categories to determine if an event such as a rollover and fire produced more fatalities or injuries than a rollover without a fire. Author

Data Systems

20050243049 Army Research Lab., Aberdeen Proving Ground, MD USA

Numerical Computations of Supersonic Flow Over a Square Cross-Section Missile

Silton, Sidra I.; Sahu, Jubaraj; Aug. 1, 2005; 52 pp.; In English Contract(s)/Grant(s): Proj-622617.H8000 Report No.(s): AD-A439496; ARL-TR-3562; No Copyright; Avail.: Defense Technical Information Center (DTIC)

This report describes a computational study undertaken to determine the aerodynamics of a nonaxisymmetric missile with a square cross section. Numerical solutions have been obtained at supersonic speeds for various roll orientations and angles of attack using a two-equation Reynolds-averaged Navier-Stokes turbulence model. Numerical results show the qualitative features (vortices and cross-flow separation regions) of the flow field at various stream wise positions along the missile configurations. Aerodynamic coefficients have been obtained from the computed solutions and found to match well with the available experimental data for these configurations. These numerical results show the ability of computational fluid dynamics techniques to accurately predict the aerodynamics of nonaxisymmetric missiles with a square cross section. DTIC

Aerodynamics; Computational Fluid Dynamics; Missiles; Supersonic Flow

Source: NASA.