Accession Number:

ADA210232

Title:

ELectrothermal Guns -- A Theoretical Investigation of Factors for Optimal Performance

Descriptive Note:

Technical rept.

Corporate Author:

ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s):

Report Date:

1989-06-01

Pagination or Media Count:

60.0

Abstract:

The electrothermal ET gun or electrothermal accelerator is an advanced propulsion concept in which an electrically generated high pressure and temperature plasma interacts with a carefully chosen working fluid to produce the necessary gases to accelerate the projectile. In theory the combustion process is completely controlled by the electrical power input used to generate and sustain the plasma. Constant breech pressure and resulting optimal velocity should be obtainable by tailoring the power input for a given working fluid. Selecting working fluids which result in low molecular weight gases reduces the energy expended in accelerating the gases. This report, using an appropriately modified interior ballistic code, investigates several aspects of the electrothermal gun process. Conditions required of the electrical input and working fluid necessary to achieve the ideal constant breech pressure and optimal velocity are considered. The sensitivity of ballistic performance and gas temperature for the electrothermal process is determined for perturbations in several factors felt to be critical to ET performance. Differences arising from using non-energetic endothermic or energetic exothermic working fluid are addressed. Results of the computer simulations indicate that an ET gun can out perform conventional solid propulsion technology. The simulations indicate that the electrical power input required to drive the constant breech pressure is feasible. One of the critical factors in ET gun performance is reproducible plasmaworking fluid interaction, impacting not only projectile velocity and pressure profiles, but more significantly, gas temperature.

Subject Categories:

  • Guns

Distribution Statement:

APPROVED FOR PUBLIC RELEASE