System for the active setting of a radial clearance size and aircraft engine with a system for the active setting of a radial clearance size

Patent metadata

Field	Value
Publication number	US-10428675-B2
Application number	US-201615234760-A
Country	US
Kind code	B2
Filing date	Aug 11, 2016
Priority date	Aug 13, 2015
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

A system for the active setting of a radial clearance size between a blade tip of at least one compressor stage and/or at least one turbine stage of an aircraft engine and a housing that surrounds the at least one compressor stage and/or the at least one turbine stage is provided. The system comprises a model-based setting device, wherein the time-dependent clearance size can be approximated by the model-based setting device, with only those influencing variables being taken into account that have a time-dependent deformation behavior which is equal to or slower than the time-dependent deformation behavior of the housing. The clearance size in the cold state serves as the set point, with the clearance size being reduced by at least one previously saved value of a clearance proportion, which is determined at maximal thrust of the aircraft engine.

First claim

The invention claimed is:

1. A system for an active setting of a radial clearance dimension between a blade tip of at least one chosen from a compressor stage and a turbine stage of an aircraft engine, and a housing surrounding the at least one chosen from the compressor stage and the turbine stage, the system comprising:
a model-based setting device configured and programmed for:
approximating the radial clearance dimension using an influencing variable with a time-dependent deformation behavior equal to or slower than a time-dependent deformation behavior of the housing,
including:
a previously saved radial clearance proportion determined at a maximal thrust of the aircraft engine, and
a radial clearance dimension set point based on the radial clearance dimension in a cold state,

calculating a reduced radial clearance dimension from the radial clearance dimension set point using the previously saved radial clearance proportion,
calculating a control variable for controlling a cooling system of the at least one chosen from the compressor stage and the turbine stage based on the reduced radial clearance dimension, and
controlling the cooling system based on the control variable.

2. The system according to claim 1 , wherein the aircraft engine further comprises a rotor disc located in the at least one chosen from the compressor stage and the turbine stage;
wherein the influencing variable is a thermal behavior of the rotor disc; and
wherein the model-based setting device further includes a relationship for the thermal behavior of the rotor disc and a relationship for a thermal behavior of the housing.

3. The system according to claim 1 , wherein the aircraft engine further comprises a rotor disc located in the at least one chosen from the compressor stage and the turbine stage;
wherein the influencing variable consists of a thermal behavior of the rotor disc; and
wherein the model-based setting device further includes a relationship for the thermal behavior of the rotor disc and a thermal behavior of the housing.

4. The system according to claim 1 , wherein the aircraft engine includes a structural component located in the aircraft engine;
wherein the influencing variable is a time-dependent deformation behavior of the structural component; and
wherein the model-based setting device models the time-dependent deformation behavior of the structural component by a linear step response.

5. The system according to claim 1 , wherein the model-based setting device determines the radial clearance dimension set point exclusively from a value independent of a current thrust state of the aircraft engine.

6. The system according to claim 1 , wherein the aircraft engine further comprises a rotor disc and a housing; and wherein the previously saved radial clearance proportion is determined by at least one chosen from a thermal behavior of a blade, a deformation behavior of the rotor disc located in the at least one chosen from the compressor stage and the turbine stage, a thermal behavior of an inlet device located inside the housing, and a pressure-dependent behavior of the housing.

7. The system according to claim 1 , further comprising a housing, wherein the housing includes at least one inlet device.

8. The system according to claim 7 , wherein the inlet device is a liner.

9. The system according to claim 7 , wherein the inlet device is a segment comprising a liner.

10. The system according to claim 1 , wherein at least one chosen from a calculated value and a measured value for at least one chosen from a temperature, a pressure, a speed, and a rotational speed are used in determining the control variable.

11. The system according to claim 1 , wherein the radial clearance dimension is taken into account in an input value of the model-based setting device.

12. An aircraft engine with at least one system according to claim 1 .

Assignees

• Rolls Royce Deutschland Ltd & Co Kg

Inventors

• Szarvasy Ivo

Classifications

• F05D2220/323

  for aircraft propulsion, e.g. jet engines · CPC title

• F04D29/582

  specially adapted for elastic fluid pumps · CPC title

• F01D11/24 Primary

  by selectively cooling-heating stator or rotor components · CPC title

• F05D2260/81

  Modelling or simulation · CPC title

• F04D29/642

  by adjusting the clearances between rotary and stationary parts · CPC title