SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 43, ISSUE 26 - DECEMBER 30, 2006

20 SPACECRAFT PROPULSION AND POWER
Includes main propulsion systems and components, e.g., rocket engines; and spacecraft auxiliary power sources.

For related information see also 07 Aircraft Propulsion and Power, 28 Propellants and Fuels, 15 Launch Vehicles and Launch Operations, and 44 Energy Production and Conversion.

20050244354 Lawrence Livermore National Lab., Livermore, CA USA

Propagation of Axially Symmetric Detonation Waves

Druce, R. L.; Roeske, F.; Souers, P. C.; Tarver, C. M.; Chow, C. T. S.; Jun. 26, 2002; 16 pp.; In English Report No.(s): DE2005-15013458; UCRL-JC-145022; No Copyright; Avail.: National Technical Information Service (NTIS)

The properties of non-ideal explosives sometimes make them more difficult to utilize, but these same properties greatly reduce the chance of unintended reaction or detonation, both in utilization and in storage. TATB is such an explosive, having a reaction zone \g1mm. There is an ongoing study at Lawrence Livermore National Laboratory (LLNL) of the detonation output properties of UFTATB boosters. The study includes boosters of various ages and powder batches. Since the ability of the detonation wave to burn uniformly throughout the main charge high explosive is one of the properties that can materially affect performance, we are monitoring parameters that will be affected by corner turning in the booster. Diagnostics include velocimetry at five discrete points and a streak camera. The positions of the velocimeter probes were chosen to provide data at several points on a line of constant longitude on the booster. The streak camera view was chosen to provide timing confirmation and to provide a link with experiments conducted previously with only streak camera diagnostics. It has been shown that anomalies in the detonation wave are accentuated at reduced temperature. For that reason, we detonated boosters at ambient temperature, -20 degrees C and -54 degrees C to study the effect of temperature as the boosters age. NTIS

Axisymmetric Flow; Detonation Waves; Explosives; Tatb

20050244617 Air Force Research Lab., Edwards AFB, CA USA

Health Management Issues and Strategy for Air Force Missiles (Technical Paper)

Ruderman, Gregory; Jul. 5, 2005; 16 pp.; In English Contract(s)/Grant(s): F04611-98-C-0005; Proj-1011 Report No.(s): AD-A440133; No Copyright; Avail.: Defense Technical Information Center (DTIC)

As so-called 'wooden rounds', which are intended to sit stably in storage for extended periods and then function precisely as desired, at a moment's notice, Air Force missiles would appear to be an ideal application for health monitoring. However, solid rocket motors that serve as the propulsion system for these missiles present a number of unique challenges for the development of integrated vehicle health monitoring systems. Mechanical and chemical complexity, long service lives, aging materials, and designs with small margins are typical for solid motors. But the payoff for health monitoring is extreme as well. Maintaining a healthy and capable fleet-ensuring the viability of the missiles in the fleet while not retiring or destroying good assets before it is necessary could save as much at 50% in costs over a 60-year life cycle. In this paper, a number of the unique aspects of solid rocket motors will be explored, the difficulties and successes in development of sensors and diagnostic systems will be discussed, and a path to further continue development of these systems will be proposed. DTIC

Health; Missiles; Solid Propellant Rocket Engines

Source: NASA.