Liquid rocket engine injector with variable flow area
AssigneeBlue Origin, LLC
InventorsMark David Horn, Adam Keith Norman
Life of this patent
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Abstract
A variable flow area injector for a liquid rocket engine. The injector has a poppet with a variable outer width portion and a housing with a variable inner width portion. An annular flow path is defined between the variable width portions. Increased throttling of the engine passively increases the annular flow area of the injector by forcing the poppet in a distal direction. Decreased throttling allows a restoring spring to move the poppet in a proximal direction to decrease the annular flow area. A bellows can be included to dampen movement of the poppet. The bellows may be in a propellant-filled cavity separate from the main propellant flow path and have a series of openings through which the separate propellant flows.
Claims1
A rocket combustion chamber injector having a passively varying flow area, the injector comprising:
- a housing comprising a sidewall extending along a longitudinal axis between a proximal end and a distal end, the sidewall comprising a variable inner width portion and a plurality of ports arranged radially about the longitudinal axis near the variable inner width portion, the plurality of ports configured to receive a propellant along a propellant flow path that extends from the plurality of ports towards the distal end of the housing;
- a poppet extending axially between a proximal end and a distal end, the poppet moveable within the housing along the longitudinal axis, the distal end of the poppet having a variable outer width portion located radially inwardly of the variable inner width portion of the housing to define therebetween an annular flow area of the propellant flow path, wherein the variable outer width portion is configured such that propellant flowing along the propellant flow path around the variable outer width portion applies a first axial force on the distal end of the poppet;
- a spring coupled to the proximal end of the poppet within the housing and configured to apply a second axial force on the proximal end of the poppet;
- and
- a bellows located within a cavity at the proximal end of the housing, the cavity configured to receive propellant therein, the bellows coupled to the proximal end of the poppet and located outside of the propellant flow path, and the bellows comprising a plurality of openings through which propellant is configured to be transmitted to dampen movement of the poppet along the longitudinal axis,
- wherein the poppet is configured to move toward the distal end of the housing in response to the first axial force exceeding the second axial force and thereby increase the annular flow area, and wherein the poppet is configured to move toward the proximal end of the housing in response to the second axial force exceeding the first axial force and thereby decrease the annular flow area.
Dependencies are inferred from the claim text.