Controlled temperature rocket nozzle
AssigneeVolvo Aero Corporation
InventorsJan Häggander, Lars-Olof Pekkari
Life of this patent
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Abstract
A rocket nozzle having an axial double bell shape. The nozzle includes a first bell shape, a second bell shape and an inflection point where the first bell shape and the second bell shape meet. The inflection point is located between a location at the area ratio ε=10 and a location at 0.85×εmax of the nozzle, where ε is the narrowest cross-sectional area of the nozzle. The first bell shape and the second bell shape both have a contour line having an outwardly directed curvature of between 2 and 7 at the inflection point.
Claims12
A rocket nozzle having an axial double bell shape for controlling a wall temperature of the rocket nozzle, the rocket nozzle comprising;
- a first bell shape;
- a second bell shape downstream of the first bell shape;
- and
- an inflection point where the first bell shape and the second bell shape meet, the wall temperature being controlled by the inflection point located between a location at the area ratio ε=10 and a location at 0.85×εmax of the nozzle, where ε=1 is the narrowest cross-sectional area of the nozzle;
- and by the curvature between the first bell shape and the second bell shape changing outwardly directed between 2 degrees and 7 degrees at the inflection point,
- wherein cooling is provided downstream of the inflection point by the change of curvature, and no active cooling is provided.
A rocket nozzle having an axial double bell shape for controlling a wall temperature of the rocket nozzle, the rocket nozzle comprising:
- a first bell shape;
- a second bell shape downstream of the first bell shape;
- an inflection point where the first bell shape and the second bell shape meet, the inflection point being located between a location at the area ratio ε=10 and a location at 0.85×εmax of the nozzle, where ε=1 is the narrowest cross-sectional area of the nozzle;
- and
- means for cooling the rocket nozzle, wherein the cooling means comprises on the second bell shape an outwardly directed change in curvature of between 2 degrees and 7 degrees at the inflection point, whereby a wall temperature of the nozzle downstream of the inflection point is reduced sufficiently to allow use of a wall material less temperature resistant than would be required without the outwardly directed curvature change.
A rocket nozzle having an axial double bell shape for controlling a wall temperature of the rocket nozzle, the rocket nozzle comprising:
- a first bell shape;
- and
- a second bell shape downstream of the first bell shape;
- wherein an inflection point is provided where the first bell shape and the second bell shape meet, the inflection point being located between a location at the area ratio ε=10 and a location at 0.85×εmax of the nozzle, where ε=1 is the narrowest cross-sectional area of the nozzle, the inflection point providing means for cooling the rocket nozzle, wherein the cooling means comprises on the first bell shape and the second bell shape a discontinuity in the meridional plane of a contour of the nozzle whereby the curvature between the first bell shape and the second bell shape changes outwardly directed between 2 degrees and 7 degrees at the inflection point, the discontinuity providing the means of cooling the nozzle, and wherein no active cooling is provided.
A method for cooling a rocket nozzle, the method comprising:
- providing the nozzle with a first bell shape;
- providing the nozzle with a second bell shape;
- and
- cooling the nozzle by providing the nozzle with an inflection point where the first bell shape and the second bell shape meet, the inflection point being located between a location at the area ratio ε=10 and a location at 0.85×εmax of the nozzle, where ε=1 is the narrowest cross-sectional area of the nozzle, wherein from the first bell shape to the second bell shape a contour line changes outwardly between 2 degrees and 7 degrees at the inflection point.
Dependencies are inferred from the claim text.