Is the time when intake and exhaust valve remain oper during the exhaust stroke.
Is the time when intake and exhaust valve remain oper during the exhaust stroke.
600 rpm / 60 = 10 revs per second. The intake valve opens on every other revolution (2 revolutions for every four-stroke cycle). This results in 5 intake valve openings per second!
While there may be some overlap of valve opening timing, generally speaking, the exhaust valve opens after the power stroke, and the intake valve opens after the exhaust stroke. Recap... We start the combustion cycle of a standard 4-stroke engine with the intake stroke, the intake valve is open and the vacuum created by the downward movement of the piston draws in the air/fuel mixture from the intake manifold. The intake valve closes as the piston rounds bottom dead center and the compression stroke begins on the upward movement of the piston. At or near the top of the compression stroke, the spark plug fires (both valves are closed at this point) and begins the downward power stroke. As the piston rounds bottom dead center again, the exhaust valve opens to allow the piston to push out the exhaust gasses during the upward exhaust stroke. As the piston gets to the top, the exhaust valve closes and the intake valve opens to start the process over again.
The purpose of butter fly valve is to maintain one way opening during induction stroke and exhaust stroke.
Is the time when intake and exhaust valve remain oper during the exhaust stroke.
AV valves close during the systole phase of the cardiac cycle.
If im not mistaken, during the power stage the intake and exhaust valves are both closed. the intake valve opens pulling air into the cylinder (cycle one) and the exhaust valve opens (cycle 4) to relase the air fuel mix that was ignited.
Closed
valve timing diagram of two stroke engine
A four stroke engine has four cycles. Intake cycle, compression cycle, power cycle, and exhaust cycle. Each corresponds to one full stroke of the piston; therefore, the complete cycle requires two revolutions of the crankshaft to complete.Here is a brief explanation on how it works.Intake cycleThe intake valve opens, the piston moves downward and fuel and air is sucked into the cylinderCompression cycleThe Intake valve closes and the piston moves upward, compressing the fuel and air mixture.Power cycleA spark plug ignites the fuel/air mixture and the piston is forced downwards.Exhaust cycleThe piston moves upward and the exhaust valve opens, letting the fumes out of the cylinder.
"Floating Valves" refers to a condition in which the valve-springs fail to fully close the valves, allowing them to "float" during the stroke cycle. Floating valves can result in valve-piston contact with consequent catastrophic mechanical damage. This is caused by revving the engine past it's red-line, or the maximum RPMs the engine was designed to run.