Scavenging and turbocharging
Q. How the exhaust of one cylinder is prevented from interfering the scavenging of another in the pulse system?
Answer: In pulse system, the exhaust of one cylinder is prevented from interfering the scavenging of another as follows. – Exhaust system is tuned so that the manifold pressure pulsation is not reflected back to engine as backpressure. – As the exhaust valve of a diesel engine opens, the gases in the cylinder rapidly expand and gain velocity andkinetic energy as they pass into the exhaust pipe. – As the exhaust gas travels through the manifold it causes partial vacuum behind it. – The cylinders are so connected to a common exhaust pipe so that the exhaust valve of the second cylinder is opened when the exhaust from the first cylinder has created a vacuum in the pipe – Exhaust from the second cylinder will be discharged more easily. – Thus the tuned exhaust system with the exhaust pipes a suitable length and arranging for two or three cylinder with suitable exhaust valve timing prevented from interfering the others.