A Caltech Library Service

An experimental investigation of unstable combustion in solid propellant rocket motors

Brownlee, W. Grant and Marble, Frank E. (1960) An experimental investigation of unstable combustion in solid propellant rocket motors. In: Solid propellant rocket research : a selection of technical papers based mainly on a symposium of the American Rocket Society. Progress in astronautics and rocketry. No.1. Academic Press , New York, pp. 455-494. ISBN 9781600862571.

[img] PDF (Author's copy) - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


Unstable combustion in solid propellant rocket motors is characterized by high frequency chamber pressure oscillations, often accompanied by changes in the mean burning rate. Experiments with casebonded, cylindrically perforated motors using a polysulfide, ammoniumperchlorate propellant were reproducible as a result of careful manufacturing control and extended propellant curing time. In these motors the oscillations were in the fundamental standing tangential mode and were accompanied by increases in the average burning rate. At sufficiently high pressure levels all firings were stable. Reduction of the operating level led to mild instability. A sufficient further reduction produced a sudden change to maximum instability. Continued reduction in pressure level from this point resulted in a gradual decrease in the degree of instability but it could not be experimentally verified that a low pressure stable region existed. The levels at which these events took place were frequency dependent and generally increased as the tangential frequency was reduced. At a given operating leve1, the instability became less severe when the grain length was reduced below a critical value. Increasing the length above the critical value did not affect the level at which the motors became stable. The pressure levels for stability and for maximum instability moved to lower values with decreases in the propellant grain temperature in a manner not entirely accounted for by the effect of grain temperature on burning rate. Stable, mildly unstable and severely unstable operation was observed throughout the range -80°F to 180°F. The maximum instability decreased with grain temperature.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Additional Information:© 1960, AIAA.
Group:Guggenheim Jet Propulsion Center
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Guggenheim Jet Propulsion Center UNSPECIFIED
Series Name:Progress in astronautics and rocketry
Issue or Number:1
Record Number:CaltechAUTHORS:20110111-110838368
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:21697
Deposited By: Ruth Sustaita
Deposited On:31 Jan 2011 19:52
Last Modified:09 Nov 2021 15:59

Repository Staff Only: item control page