Module 1,2,3,4 Flashcards
(36 cards)
4 major classes of engines
Opposed
Radial
V type
In-line
Major difference between air cooled and liquid cooled engines?
Air cooled has fins on the cylinders, liquid cooled does not
What are the engine designations?
G - Geared nose section T - Turbocharged S- Supercharged I - Fuel Injected O - Opposed type L - Lefthand rotation V - Vertical Helicopter H - Horizontal Helicopter A - Aerobatic ### - cubic inches displacement
Where is most efficiency lost?
The exhaust
Orientation and counting of the cylinders is relative to where?
The rear / The cockpit
Purpose of crankcase?
Supports the crankshaft, provides enclosure for all parts and oil
Purpose of crankshaft?
Turns reciprocating motion from pistons into rotational motion
Purpose of connecting rod?
Transfers that linear motion from the piston to the crankshaft
What type of engine has an articulating rod?
Radial
How many crankpins does a opposed & radial engine have?
Opposed = however many pistons Radial = one
What are the 2 functions of a piston?
Draw in mixture into cylinder, compress it, then purge cylinder
Transmit force from combustion to crankshaft through connecting rod
What are the function of piston rings?
Provide a seal to reduce oil seepage into combustion chamber, prevent leakage of gases into crankcase, transfer heat from piston to cylinder walls
2 major parts of piston assembly?
Cylinder head & barrel
Which cylinder valve has a larger diameter?
Exhaust
Why is the exhaust valve hollow?
It holds metallic sodium that melts to help dissipate heat
Purpose of valve spring?
Keeps valve closed
Name components of valve mechanism
Camshaft
Rocker arm
Name components of valve train
Camshaft Cam follower Hydraulic valve filter Pushrod Valves Valve springs Rocker Arm
Purpose of accessory gear box?
Hold accessories such as vacuum pumps, oil pumps, governors, magnetos, etc.
Purpose of reduction gear box?
Slows down the propeller speed so propeller tip speed is not exceeded
List the 3 types of bearing
Plain bearing
Roller bearing
Ball bearing
Which bearing carries both radial and thrust loads?
Ball bearing
What is a heat engine?
Converts heat into mechanical energy
Approx thermal efficiency of an internal combustion engine?
25-30% useful work
40-45% goes out exhaust
5-10% removed by oil
15-20% removed by fins
