Railgun performance with a two-stage light-gas gun injector

Conference · Mon Apr 02 00:00:00 EDT 1990 · IEEE Transactions on Magnetics

DOI:https://doi.org/10.1109/20.100988· OSTI ID:6875072

Hawke, R. S. ^[1]; Susoeff, A. R. ^[1]; Asay, J. R. ^[2]; Ang, J. A. ^[2]; Hall, C. A. ^[2]; Konrad, C. H. ^[2]; Wellman, G. W. ^[2]; Hickman, R. J. ^[3]; Heath, W. A. ^[3]; Martinez, J. R. ^[3]; Sauve, J. L. ^[4]; Vasey, A. R. ^[4]; Shahinpoor, M. ^[5]

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1. Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
2. Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
3. Ktech Corporation, Albuquerque, NM (United States)
4. EG&G Energy Measurements, Inc., Albuquerque, NM (United States)
5. University of New Mexico, Albuquerque, NM (United States)

This paper summarizes the results obtained with the HELEOS railgun which uses a two-stage light-gas gun (2SLGG) as an injector. The high velocity 2SLGG injector pre-accelerates projectiles up to ~7 km/s. The high injection velocity reduces the exposure duration of the railgun barrel to the passing high temperature plasma armature, thereby reducing the ablation and subsequent armature growth. The 2SLGG also provides a column of cool, high pressure hydrogen gas to insulate the rails behind the projectile, thereby eliminating restrike. A means to form an armature behind the injected projectile has been developed. In preliminary tests, the third stage railgun has successfully increased the projectile velocity by 1.35 km/s. Extensive diagnostics have been used to determine the behavior of the armature and track the launcher's performance. In some cases, velocity increases in the railgun section have been achieved, which are in close agreement with theoretical predictions, whereas in other experiments deviations from theoretical have been observed. The reasons for and implications of these results are addressed. Recent tests are reported.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE Office of Defense Programs (DP)
• DOE Contract Number: W-7405-ENG-48; AC04-76DP00789
• OSTI ID: 6875072
• Report Number(s): UCRL-101932-Rev.1; CONF-9004136--9-Rev.; ON: DE90016211
• Journal Information: IEEE Transactions on Magnetics, Journal Name: IEEE Transactions on Magnetics Journal Issue: 1 Vol. 27; ISSN 0018-9464
• Publisher: Institute of Electrical and Electronics Engineers. Magnetics Group
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420200* -- Engineering-- Facilities
Equipment
& Techniques
ABLATION
ACCELERATORS
BOUNDARY LAYERS
COMPARATIVE EVALUATIONS
CURRENT DENSITY
DRAG
ELECTRIC POTENTIAL
ELECTROMAGNETIC FIELDS
EVAPORATION
LAUNCHING
LAYERS
MEASURING METHODS
PERFORMANCE TESTING
PHASE TRANSFORMATIONS
PLASMA
PRESSURE EFFECTS
PROJECTILES
RAILGUN ACCELERATORS
STABILITY
SURFACE PROPERTIES
TESTING
VELOCITY