Use of a sampling feedback system for stabilization of low frequency oscillations in liquid monopropellant rocket motors

• Main Author: Fernandez, Raymond Caesar
• Format: Others
• Published: 1953
• Online Access: https://thesis.library.caltech.edu/1462/1/Fernandez%2CC_1953.pdf; Fernandez, Raymond Caesar (1953) Use of a sampling feedback system for stabilization of low frequency oscillations in liquid monopropellant rocket motors. Engineer's thesis, California Institute of Technology. doi:10.7907/PZEC-N445. https://resolver.caltech.edu/CaltechETD:etd-04232003-090202 <https://resolver.caltech.edu/CaltechETD:etd-04232003-090202>

Instability in liquid monopropellant rocket motors may be corrected by the use of a feedback servomechanism. This mechanism consists essentially of a pressure pickup which senses pressure oscillations in the combustion chamber, an amplifier and a variable capacitance in the feed line. It is shown that a feedback system with an arbitrary sampling circuit which causes the capacitance in the line to complete its own cycle of variation once for every several cycles of combustion pressure oscillations can be made to stabilize the oscillations for all values of combustion time lag for a particular motor. It is believed that this system of stabilization may be applied to monopropellant motors in general.