transportation technology engine operation: 4 stoke cycle c. stemmler 4 four stroke engine
Post on 28-Dec-2015
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Transportation Technology
Engine Operation:4 Stoke Cycle
C. Stemmler
4 Four Stroke Engine
4 Stroke Cycle
“cycle” is considered to be a repetitive series of operations
4 Stroke - requires the piston to move four times--up then down--four times to complete one cycle (two revolutions of the crankshaft)
most automotive & diesel truck engines are 4 stroke engines--due to emission laws
4 Stroke Cycle -- Intake Stroke
Piston Direction downTDC to BDC
Intake Valve open
Exhaust valve closed
Movement of gases enters cylinder
Pressure 14 hg. of vacuum
Intake valve
Compression Stroke
Piston Direction UpBDC to TDC
Intake Valve closed
Exhaust valve closed
Movement of gases squeezed Pressure 120 to 150
psi
Exhaust valve
Power Stroke
Piston Direction DownTDC to BDC
Intake Valve closed
Exhaust valve closed
Movement of gases rapid expansion
Pressure 800 to 1000 psi
Exhaust Stroke
Piston Direction UpBDC to TDC
Intake Valve closed
Exhaust valve open
Movement of gases expelled or pushed out
Pressure 20 to 30 psi
The camshaft turns in one complete cycle - which is degrees of crankshaft rotation.
The crankshaft turns degrees during one stroke.
There are crankshaft revolutions in one cycle - which is degrees of crankshaft rotation rotation.
4 Stroke Cycle - Complete
two720
180
once720
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