🔍 Key Concepts

• Flow of air and exhaust through a two-stroke diesel cylinder in the different figures • Difference between ports in the cylinder liner and separate valves in the cylinder head • Function of scavenging in removing exhaust gases and bringing in fresh air

💭 Think About

• Compare where the gases enter and exit the cylinder in Fig. 3 versus Fig. 4. What is happening at the top of the cylinder and what is happening at the side where "S" is located? • Look at the arrows around labels M, T, V, and S in Fig. 4. Do they show fresh air coming in or burned gases going out? • Which of the choices would normally be built as passages (slots/ports) in the liner itself, and which would usually be separate external equipment?

✅ Before You Answer

• Verify whether the arrows at "S" show incoming air or outgoing exhaust gas. • Check if an after cooler would normally be drawn as part of the cylinder liner, or as separate piping/heat-exchanger equipment outside the liner. • Confirm whether a valve would be shown as a movable element in the head, versus fixed ports cut into the side of the liner.