1. SNS COLLEGE OF ENGINEERING Coimbatore-107 Subject: Thermal Engineering
Valve timing and port timing diagrams, PV diagrams-actual and theoretical BY
Prabhakaran.T
AP/MECH

2. Guess what??

3. VALVE TIMING
In a piston engine, the valve timing is the precise timing of the opening and closing of the valves. In an internal combustion engine those are usually poppet valves and in a steam engine they are usually slide valves or piston valves.

4. 4 stroke diesel

5. 4 STROKE SI ENGINE

6. PORT TIMING DIAGRAM
Since the one cycle is completed in one revolution of the crank, the sequence of operation of the ports can be represented in a circle (360°). This representation is known as a port timing diagram.
The port timing diagram gives an idea about when a phase of the two-stroke cycle takes place.

7. PORT TIMING DIAGRAM

8. Activity
Find the bike logo………………………

11. Actual PV diagram SI Engine

12. Actual PV diagram CI Engine

13. Actual PV diagram of 2 stroke petrol engine

14. Actual PV diagram of 2 stroke diesel engine

15. THANK U