Thermal actuated valve for clearance control
AssigneeGeneral Electric Company
InventorWilliam R. Patterson
Life of this patent
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Abstract
A shroud closely surronding a high thermal inertia rotor is provided with a support structure having low thermal inertia characteristics. The support structure is selectively exposed to different temperature mediums during transient operation by way of a thermal actuated valve so as to cause a rapid growth thereof during periods of engine acceleration and a slow shrinkage thereof during periods of deceleration of the engine. In this manner the clearance relationship between the shroud and enclosed rotor is maintained at a minimum during periods of steady-state and transitional operation to thereby increase the efficiency of the combination.
Claims13
An improved gas turbomachine of the type having a relatively high thermal inertia rotor disposed in close clearance relationship within a stator for operation over a range of temperatures and speeds wherein the improvement comprises:
- a. a shroud surrounding a portion of the rotor;
- b. a shroud support for positioning said shroud radially with respect to said rotor, said shroud support having a relatively low thermal inertia and adapted to grow radially outward during periods of machine acceleration and shrink during periods of deceleration;
- and
- c. valve means responsive to machine acceleration and deceleration for directing a relatively hot fluid medium over said shroud support during periods of machine acceleration and away from said shroud support during periods of machine deceleration so that said shroud support has a relatively fast growth rate and a relatively slow shrinkage rate.
An improved gas turbomachine of the type having a relatively high thermal inertia rotor disposed in close clearance relationship within a relatively low thermal inertia stator for operation over a range of temperatures and speeds wherein the improvement comprises:
- a. a shroud surrounding a portion of the rotor;
- b. a relatively low thermal inertia shroud support for radially positioning said shroud with respect to said rotor;
- c. means for selectively conducting a relatively hot fluid over said shroud support to cause thermal expansion thereof;
- and
- d. valve means responsive to the temperature of said thermal fluid to cause operation of said conduction means during periods of machine acceleration and cease operation thereof during periods of machine deceleration.
Dependencies are inferred from the claim text.