Method and apparatus for improving acceleration in a multi-shaft gas turbine engine

Patent · Tue May 27 04:00:00 EDT 1986

OSTI ID:5702557

Blizzard, C A.M.

A method is described for improving the acceleration of a free turbine, gas turbine engine from a minimum power condition to a maximum power condition. The gas turbine engine is provided with a diaphragm bleed valve means having a first chamber means and a second chamber means defined by a diaphragm, the first valve chamber means communicating with the compressor and a pre-swirl station and operative to permit or block bleed air from the compressor to the bleed air station, a high pressure air source communicating with the second chamber and with a control valve operatively connected to a governor which in turn is connected to a load sensing means. This includes the steps of proportionally supplying bleed air from a compressor of the gas turbine engine to a pre-swirl station as the low load is sensed causing the governor to open the control valve, thus maintaining low pressure in the second chamber such as to permit the first chamber to be open. A jet flap is created at the pre-swirl station thereby maintaining a constant compressor speed matched with the power turbine loads at low power requirements; sensing an increased load and thus higher power requirements at the output of the gas turbine engine, thus causing the governor to gradually close the control valve and building up the pressure in the second chamber which forces the first chamber to close; and progressively eliminating the pre-swirl as higher power requirements are required.

• Assignee: Pratt and Whitney Canada, Inc., Longueuil
• Patent Number(s): US 4590759
• OSTI ID: 5702557
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330103* -- Internal Combustion Engines-- Turbine
ACCELERATION
AIR FLOW
COMPRESSORS
CONTROL
CONTROL EQUIPMENT
ENGINES
EQUIPMENT
FLOW REGULATORS
FLUID FLOW
GAS FLOW
GAS TURBINE ENGINES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
MACHINE PARTS
PRESSURE CONTROL
SHAFTS
SPEED REGULATORS
VALVES
VELOCITY
VORTEX FLOW