INDICATOR DIAGRAM

 indicator diagram

•  At the same time it will indicate pressure and the position of piston.

Purpose:

• To indicate the power developed in the system (cylinder).
• To indicate the pressure maximum (Pmax) and compression pressure
• To find the exhaust and scavenging condition
• To evaluate the combustion process.

 

Types of indictor diagram.

• Draw card 
• Power card
• Compression card
• Light spring diagram

DRAW CARD 

 

• Its used to find the Pmax & Pcom accurately
• With this draw card we can find the ignition delay,fuel pump timing and after burning and the loss of compression.
• Its 90° out off phase with piston movement.

POWER CARD

• Its used to find the indictor power.
• And to find the peak pressure and compression pressure.
• Its in-phase with piston with fuel on.
• It can be find by planimeter.

COMPRESSION CARD

• Its used to find the compression pressure.
• Ans the cylinder thickness.
• Its in-phase cut off fuel and reduce rpm.

LIGHT SPRING DIAGRAM

• Its used to find the pressure variation in the cylinder. With respect to scavenge and exhaust manifold.
• It is in-phase with light spring in fuel on .
• It will show the chocks in scavenge manifold and exhaust valve chocks and less air.

SURVIVER MAY ASK

Why is not possible to take power card in 4-stroke engine?

• 4 stroke piston moves 2 times to TDC in one cycle. So we can't able to take.