Analysis of a Gas Generator System.

Abstract

A small gas generator suddenly failed in acceptance tests after a string of successes. Intensive tests and rough calculations said that heat transfer to the cold surroundings, coupled with a change in burning-rate exponent at low pressure, caused the failure. Two math models, a lumped parameter model and a full one-dimensional fluid mechanics model were devised to explain the interaction among combustion, heat transfer, and fluid mechanics. The models predict that a reasonable estimate of heat loss does not, by itself, explain the failures. The success of an isolation venturi can only be partially explained by heat transfer. Suspicion then rests on the assumption of equilibrium combustion thermodynamics at the very cold temperatures where the failures occurred. Variations with age and propellant batch are still not exonerated, even though the critical problem seems to have been solved.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1985
Accession Number
ADA156999

Entities

People

  • C. W. Nelson
  • D. E. Kooker

Organizations

  • Ballistic Research Laboratory

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Burning Rate
  • Chemical Engineering
  • Chemistry
  • Combustion
  • Combustion Chambers
  • Combustion Products
  • Fluid Flow
  • Fluid Mechanics
  • Heat Energy
  • Heat Transfer
  • Heat Transfer Coefficients
  • Ignition
  • Jet Propulsion
  • Mach Number
  • Military Research
  • Nozzles
  • Thermodynamics

Readers

  • Combustion and Flow Dynamics.
  • Fluid Dynamics.
  • Software Engineering