Accession Number:

ADA019213

Title:

External Catalyst Breakup Phenomena

Descriptive Note:

Interim technical rept. Jun 1974-Apr 1975

Corporate Author:

EXXON RESEARCH AND ENGINEERING CO LINDEN NJ GOVERNMENT RESEARCH LAB

Personal Author(s):

Report Date:

1975-09-01

Pagination or Media Count:

268.0

Abstract:

The overall objective of the work in this program is to investigate the external breakup mechanisms of Shell 405 catalyst so as to establish an understanding of the phenomenon which can aid in extending catalyst life in use in monopropellant hydrazine thrusters. The program involves the joint efforts of Exxon Research and Engineering Company, McDonnell Douglas Astronautics Company and TRW Inc. The program involves both experimental and analytical studies of potential catalyst breakup mechanisms. A number of different mechanisms were identified for study following a review of the literature and other available information. To date fourteen specific mechanisms from the general areas of fluid dynamic erosion, pressure crushing, differential thermal expansion, particle movement, thermal shock and pore pressure gradients have been screened. Major breakup mechanisms or factors identified to date include particle to particle crushing as a result of various static pressure crushing forces, build- up of pressure within the catalyst pore as a result of imbibed liquid hydrazine the fact that a voided thruster bed has sufficient gas velocity for particle movement, and loss of catalyst physical properties such as crush strength with use. Other significant mechanisms or factors identified include fluid dynamic erosion from a pulsed liquid stream and from particulates in hydrazine and thermal shock during liquid quench cooldown. Five mechanisms or factors were judged not to be significant. Although the program is not completed, the results to date were examined for thruster design implications.

Subject Categories:

  • Physical Chemistry
  • Liquid Propellant Rocket Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE