Accession Number : AD0691852

Title :   ATTITUDE STABILIZATION USING A ROTATING PLUG NOZZLE.

Descriptive Note : Final rept. 1 Jan-30 Jun 69,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE AEROPHYSICS LAB

Personal Author(s) : Draim,John E.

Report Date : JUL 1969

Pagination or Media Count : 84

Abstract : A modified plug nozzle in which the plug is spinning as a gyroscopic mass is investigated. It is postulated that exhaust gas flow is modulated between the plug and the rocket casing in such a manner as to provide a stabilizing moment around the rocket center of gravity, when the rocket longitudinal axis deviates from the plug-spin axis. Lagrange equations of motion are formulated for the dynamical system described by four generalized coordinates. These equations are mechanized in an analog computer to yield plots of rocket angular motions. Critical non-dimensional parameters for the system are identified and discussed. A small demonstrator model was designed, constructed and tested, first with a smooth conical plug, and then with a conical plug having indented turning slots in the area of the exhaust annulus. Tests conducted on the model demonstrated that sufficient gyroscopic rigidity can be generated to counter the unbalanced pressure field effects around the rotating plug. (Author)

Descriptors :   (*ROCKETS, SPIN STABILIZATION), (*PLUG NOZZLES, STABILIZATION SYSTEMS), ROCKET NOZZLES, CONICAL BODIES, SPINNING(MOTION), STABILIZATION, NOZZLE GAS FLOW, MODULATION, EQUATIONS OF MOTION, THESES

Subject Categories : Rockets
      Fluid Mechanics
      Rocket Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE