Vernier duct blocker
A vernier duct blocker comprising a plurality of vanes each having a width and comprising a forward portion and an aft portion defining a plurality of gas paths each of the plurality of vanes being separated by a plurality of widths, and a rotatably movable ring interposed between the forward portion and the aft portion comprising a plurality of openings each having a width, wherein the width of one of the plurality of vanes differs from the width of another one of the plurality of vanes.
1. A vernier duct blocker comprising:
a plurality of vanes each having a width and comprising a forward portion and an aft portion defining a plurality of gas paths each of said plurality of vanes being separated by a plurality of widths; and
a rotatably movable ring interposed between said forward portion and said aft portion comprising a plurality of openings each having a width;
wherein said width of one of said plurality of vanes differs from said width of another one of said plurality of vanes.
2. The blocker of claim 1 wherein said width of one of said plurality of openings differs from said width of another one of said plurality of openings.
3. The blocker of claim 1 wherein said rotatably movable ring can be rotated about a central axis for a rotation distance.
4. The blocker of claim 3 wherein said movable ring can be positioned in a fully open position.
5. The blocker of claim 3 wherein said rotatably movable ring can be rotated about said central axis to provide a generally linear relationship between said plurality of said openings not blocked by one of said plurality of vanes and said rotation distance.
6. The blocker of claim 3 wherein said rotatably movable ring can be rotated about said central axis to provide a generally non-linear relationship between said plurality of said openings not blocked by one of said plurality of vanes and said rotation distance.
7. The blocker of claim 1 wherein each of said plurality of vanes has an airfoil shape.
8. The flow blocker of claim 1 wherein each of said plurality of vanes is located in a flowpath of a gas turbine engine.
9. The flow blocker of claim 8 wherein said flowpath is a secondary flowpath.
10. A method of controlling gas flow through a gas flowpath comprising the steps of:
providing a plurality of vanes each having a width and comprising a forward portion and an aft portion defining a plurality of gas paths each of said plurality of vanes being separated by a plurality of widths;
providing a rotatably movable ring interposed between said forward portion and said aft portion comprising a plurality of openings each having a width wherein said width of one of said plurality of vanes differs from said width of another one of said plurality of vanes; and
rotating said rotatably movable ring about a central axis to at least partially block a flow of a gas through said plurality of gas paths.