Rotor/shroud clearance control system
AssigneeGeneral Electric Company
InventorSamuel H. Davison
Life of this patent
Estimating the term…
Abstract
Cooling airflow to the shroud support apparatus is varied in response to both rotor speed and elapsed time above a predetermined level by the selective use and mixture of two air sources at different temperatures. For steady-state operation, each of four different operating modes has its prescribed cooling air delivery mode such that, generally, as the engine speed and cycle temperatures increase, so does that of the cooling air. For transient operation, a timer is employed to sequence the desired cooling air delivery modes in such a manner as to maintain optimum rotor-to-shroud clearances during the transient period.
Claims37
In combination with apparatus of the type having a variable speed rotor, a shroud, and a shroud support with the shroud surrounding the rotor, an improved air delivery system for modulating thermal growth of the shroud support comprising:
- (a) means for sensing the operating speed of the rotor;
- (b) means for timing the operation of the rotor after an acceleration;
- and
- (c) means responsive to said timing means and to the speed of the rotor for varying the temperature of the air.
A method for modulating thermal growth of a support for a rotor surrounding shroud comprising the steps of:
- (a) sensing the operating speed of the rotor;
- (b) timing the operating of the rotor after an acceleration thereof;
- (c) varying the temperature of an air supply in response to said time and to the operating speed of the rotor;
- and
- (d) providing for the flow of said air supply to the shroud support.
An improved turbomachinery apparatus of the type having a rotor, a stationary shroud, a shroud support structure and means for changing the temperature of the support structure to regulate the clearance between the rotor and the shroud wherein the improvement comprises:
- (a) means for sensing the operating speed of the rotor;
- (b) means for timing the operation of the rotor after an acceleration;
- (c) a first source for providing air at a first temperature;
- (d) a second source for providing air at a second temperature higher than said first temperature;
- (e) mixer means for providing a flow of air from selective combinations of said first and second temperature air wherein said mixer means is responsive to the timing means and to the speed of the rotor;
- and
- (f) means for introducing the flow of air on the shroud support structure to modulate its thermal growth.
Dependencies are inferred from the claim text.