13 terms

Engine Cooling Systems

Powerplant Typical Oral Questions (ASA Powerplant 2013) O&P
What is Pressure Cooling of aircraft engine?
1.Air Cooling- Air Forced flow through:
a)Baffles &
b)Cylinder Fins by:
c)Pressure Differential across engine
Purpose of Augmentor Tube in Cooling System of aircraft reciprocating engine?
1.Augmentor Tube - Uses velocity of exhaust gases to produce:
a)Low Pressure on 1 side of engine
b)Helps pull cooling air through it
Highest temperature located in turbine engine?
Inlet to High-Pressure Turbine
How Turbine Inlet Guide Vanes & 1st-Stage Turbine Blades in some turbine engines cooled?
1.High-Pressure Compressor bleed air flows through:
a)Hollow Guide Vanes &
b)Hollow Turbine Blades
Which side of Air-Cooled Engine Cylinder has greatest amount of cooling fins?
Side of Cylinder which Exhaust Valve is Located
Done to repair bent cooling fin in cast aluminum cylinder head?
1.Leave bent cast fin alone if doesn't restrict flow of air.
2.Cast Fins -are Brittle & could Break Off
Used in Helicopter to increase amount of cooling air flows over engine cylinders?
Belt-Driven Fan
Position of Cowl Flaps on reciprocating engine when run on Ground?
Wide Open - Operating Engine on Ground
Function of majority air passing through Turbine Engine?
Majority Air used - for Cooling
How Metallic Sodium in exhaust valve aid in Transferring Heat?
1.Sodium Melts when engine is running & a)Sloshes up & down as valve operates. 3.Sodium picks up heat from valve head & a)Carries into Stem so can be:
b)Transferred to Cylinder Head &
c)Dissipated into Air
How's Structure around Turbine Engine protected from excessive heat from engine?
Insulating Blanket - Protects Structure from Excessive Heat
Function of Blast Tubes installed in Pressure Cooling System of Reciprocating Engine?
1.Blast Tubes- Direct Cooling Air to: a)Magnetos
Material is Insulation Blanket used to protect aircraft structure from heat produced by Turbine Engine?
Fiberglass Sandwiched between Sheets of Metal Foil