Rocket motor nozzle throat area control system and method
AssigneeHoneywell International Inc.
InventorsMorris G. Anderson, Jason A. Gratton, George T. Woessner
Life of this patent
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Abstract
A solid rocket motor including a combustion chamber, in which propellant is ignited to produce combustion gas, and a nozzle having a throat with an effective flow area, implements a system and method to inject gas into the nozzle throat to control its effective cross sectional flow area. Controlling the effective cross sectional flow area of the nozzle throat in turn controls combustion chamber pressure, thus the burn rate of the propellant in the combustion chamber, and thus the thrust generated thereby.
Claims22
A rocket motor, comprising:
- a motor having an inner surface defining a combustion chamber, the combustion chamber configured to receive a propellant therein and supply combustion gas upon ignition of the propellant;
- a nozzle including at least an inlet section, a primary throat, and an outlet section fluidly coupled in flow-series, the nozzle inlet section in fluid communication with the combustion chamber and including an inner surface defining a nozzle inlet passage having a convergent cross sectional flow area, the nozzle outlet section including an inner surface defining a nozzle outlet flow passage having a divergent cross sectional flow area;
- an injection duct having an inlet port, an outlet port, and an injection flow passage there between, the inlet port adapted to receive a flow of fluid, the outlet port disposed downstream of, and in fluid communication with, the primary nozzle throat;
- and
- a control valve mounted on the injection duct and moveable between at least (i) a closed position, in which the injection duct inlet port is fluidly isolated from the injection duct outlet port, and (ii) an open position, in which the injection duct inlet port is fluidly coupled to the injection duct outlet port, whereby fluid supplied to the injection duct inlet port is injected downstream of the primary nozzle throat,
- wherein the fluid is injected one of either (i) radially into the throat or (ii) into the nozzle throat tangential to combustion gas flow through the nozzle throat.
A solid rocket motor, comprising:
- a motor having an inner surface defining a combustion chamber, the combustion chamber configured to receive a propellant therein and supply combustion gas upon ignition of the propellant;
- a nozzle including a primary throat, a secondary throat, and an outlet section fluidly coupled in flow-series, the primary throat in fluid communication with the combustion chamber and having a first cross sectional flow area, the secondary throat having a second cross sectional area that is larger than the first cross sectional area;
- an injection duct having an inlet port, an outlet port, and a bypass flow passage there between, the injection duct inlet port in fluid communication with the combustion chamber, the injection duct outlet port in fluid communication with the secondary throat;
- and
- a control valve mounted on the injection duct and moveable between at least (i) a closed position, in which the injection duct inlet port is fluidly isolated from the injection duct outlet port, and (ii) an open position, in which the injection duct inlet port is fluidly coupled to the injection duct outlet port, whereby a portion of the combustion gas bypasses the nozzle primary throat and is injected into the nozzle secondary throat.
A rocket motor, comprising:
- a motor having an inner surface defining a combustion chamber, the combustion chamber configured to receive a propellant therein and supply combustion gas upon ignition of the propellant;
- a nozzle including at least an inlet section, a nozzle throat, and an outlet section fluidly coupled in flow-series, the nozzle inlet section in fluid communication with the combustion chamber and including an inner surface defining a nozzle inlet passage having a convergent cross sectional flow area, the nozzle outlet section including an inner surface defining a nozzle outlet flow passage having a divergent cross sectional flow area;
- an injection duct having an inlet port, an outlet port, and an injection flow passage there between, the inlet port adapted to receive a flow of fluid, the outlet port in fluid communication with nozzle throat;
- a control valve mounted on the injection duct and moveable between at least (i) a closed position, in which the injection duct inlet port is fluidly isolated from the injection duct outlet port, and (ii) an open position, in which the injection duct inlet port is fluidly coupled to the injection duct outlet port, whereby fluid supplied to the injection duct inlet port is injected downstream of the primary nozzle throat;
- a controller configured to supply one or more valve commands at a set periodicity;
- and
- a valve actuator coupled to receive the valve commands and operable, in response thereto, to periodically move the control valve between the open and closed positions at the set periodicity.
In a solid rocket motor including at least a nozzle having a convergent inlet port coupled to receive combustion gas from a combustion chamber, a divergent outlet port, a primary nozzle throat having a first cross sectional flow area fluidly coupled between the inlet and outlet ports, and a secondary nozzle throat having a second cross sectional flow area fluidly coupled between the primary nozzle throat and the outlet port, a method of controlling the first cross sectional flow area of the primary nozzle throat, the method comprising the steps of:
- supplying a flow of combustion gas from the combustion chamber to the convergent inlet port, whereby the combustion gas flows through the convergent inlet port, the primary nozzle throat, and the convergent outlet port to thereby generate thrust;
- and
- selectively injecting a flow of a control gas into the nozzle secondary throat, whereby the effective nozzle throat first cross sectional flow area is selectively varied.
In a solid rocket motor including at least a nozzle having a convergent inlet port coupled to receive combustion gas from a combustion chamber, a divergent outlet port, and an interposing nozzle throat having an effective flow area, a method of controlling the effective flow area of the nozzle throat, the method comprising the steps of:
- supplying a flow of combustion gas from the combustion chamber to the convergent inlet port, whereby the combustion gas flows through the convergent inlet port, the nozzle throat, and the convergent outlet port to thereby generate thrust;
- and
- injecting a flow of a control gas downstream of the nozzle throat at a predetermined periodicity, whereby the effective nozzle throat flow area is varied.
Dependencies are inferred from the claim text.