Apparatus for improving acceleration in a multi-shaft gas turbine engine

Patent · Tue Feb 03 04:00:00 EST 1987

OSTI ID:6812682

Blizzard, C A.M.

This patent describes a free turbine gas turbine engine comprising at least a compressor shaft mounting and blade stages, an output shaft mounting at least a turbine blade stage, and means for bleeding air from the compressor. The bleed valve means includes a cylinder and piston means within the cylinder, the piston having first and second faces, the first face of the piston defining with the cylinder a first valve chamber and the second face defining with the cylinder a second chamber. The means for bleeding the compressor air communicates with an inlet in the first valve chamber, hollow pre-swirl members provided upstream of the compressor. The pre-swirl members are provided with means for forming a jet flap, and an outlet is provided in the first valve chamber. The engine also comprises means communicating the outlet from the first valve chamber to the hollow pre-swirl members, means communicating a high pressure air source downstream of the compressor to an inlet in the second valve chamber, an outlet in the second valve chamber, a control valve and governor means operatively connected to the control valve. Under minimum power requirements, the governor will maintain the control valve open thereby maintaining a low pressure in the second valve chamber thus maintaining the bleed valve open to provide a jet flap and thus a pre-swirl to the compressor. When a load is being sensed, the governor will progressively close the control valve thus increasing the pressure in the second valve chamber, thereby closing the bleed valve and eliminating the pre-swirl to enable the compressor to provide a greater gas horsepower.

• Assignee: Pratt and Whitney Canada, Inc., Longeuil
• Patent Number(s): US 4640091
• OSTI ID: 6812682
• 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
CYLINDERS
ENGINES
EQUIPMENT
FLOW REGULATORS
FLUID FLOW
GAS FLOW
GAS TURBINE ENGINES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
MACHINE PARTS
PISTONS
POWER GENERATION
PRESSURE CONTROL
SHAFTS
SPEED REGULATORS
TURBINE BLADES
VALVES
VORTEX FLOW