Accession Number:

AD0760205

Title:

Nonequilibrium Cluster Formation in Rocket Exhausts

Descriptive Note:

Research memo.

Corporate Author:

GRUMMAN AEROSPACE CORP BETHPAGE NY RESEARCH DEPT

Personal Author(s):

• Oman, Richard A.
• Calia, Vincent S.

Report Date:

1973-03-01

Pagination or Media Count:

17.0

Abstract:

Crude estimates of cluster-forming kinetics based on molecular beam measurements and scaling methods indicate that very large polymers will form in the vacuum plumes of large rocket engines. Although no scaling methods exist that are properly applicable to polyatomic species, the authors have applied the monatomic species scaling concepts developed by Hagena, et al, to the molecular parameters of the H2O molecule in order to estimate its clustering behavior. These calculations indicate that the products of adiabatic combustion of H2 and O2 will form clusters of several thousand H2O molecules if allowed to expand freely to vacuum. Several experiments that could be performed to define the basic cluster-forming rates, cluster size distribution and to confirm the scaling relationships are discussed. These experiments include the use of plumes from a perfectly mixed combustion simulating a variety of rocket propellants at various scale sizes.

Descriptors:

• *WATER VAPOR
• *ROCKET EXHAUST
• *NUCLEATION
• *EXHAUST GASES
• GAS FLOW
• IONS

Subject Categories:

• Physical Chemistry
• Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE