Power Engineering Scavenging

     The clearing or sweeping out of the exhaust gases from the combustion chamber of the cylinder is known as scavenging.
     It Is necessary that cylinder should not have any burnt gases because they mixed with the fresh incoming charge and reduce its strength.
     power will be lost it he fresh charge is diluted by the exhaust gases.
     The Scavenging is necessary only in two stroke engine since piston does not help for clearing the burned gas from the cylinder.

(A)   Cross flow scavenging :

• the admission ports are provided on the sides of the cylinder and exhaust ports are kept on the opposite cylinder  will 
• the charge or air entering through the scavenge (admission) ports is directed upward which pushes out the exhaust ports a