What is a valve timing diagram for a 4 stroke engine?
As we all know in 4-stroke engine the cycle completes in 4-strokes that are suction, compression, expansion and exhaust , The relation between the valves (inlet and outlet) and piston movement from TDC to BDC is represented by the graph known as valve timing diagram.
When does the inlet valve open in an SI engine?
( SI Engine) The valve timing diagram, as shown we see that the inlet valve opens before the piston reaches TDC or in other words, while the piston is still moving up before the beginning of the suction stroke. Now the piston reaches the TDC and the suction stroke starts. The piston reaches the BDC and then starts moving up.
How many times do engine valves overlap in the entire cycle?
As we can see in the entire cycle of engine valves overlap 2 times i.e. closing of both valves during compression stroke and opening of both valves during exhaust stroke.
When does the exhaust valve close in a 4-stroke engine?
Exhaust valve closes after the piston reaches TDC. In suction stroke of 4-stroke engine the inlet valve opens 10-20 degree advance to TDC for the proper intake of air-fuel (petrol) or air (diesel) ,which also provides cleaning of remaining combustion residuals in the combustion chamber.
What are the port opening and closing timings in 2 stroke engine?
But now we are going to discuss the port opening and closing timings in the 2 stroke engine by drawing a Port Timing diagram. In two-stroke engines, the Thermodynamic cycle will be completed within the one revolution of the crankshaft. Two Stroke Engine uses ports rather than the valves. Port: Fluid can be operated inward and outward.
How does a 2 stroke engine cycle work?
The piston reaches the Bottom Dead centre (BDC). With this action, the cycle completes within the one revolution of crank and cycle repeats again. This is the theoretical port timing diagram for the 2 stroke engine. But the actual diagram will vary with the engine design and the specification.