🔍 Key Concepts

• Study the scavenge ports in the cylinder liner and the location of the exhaust valve/ports in the illustration. • Recall how air flows in cross‑flow, loop, uniflow, and return‑flow scavenging for two‑stroke diesels. • Note the direction of arrows showing scavenging air and exhaust gas paths in the diagram.

💭 Think About

• From the picture, where does fresh scavenge air enter the cylinder, and where does exhaust gas leave? Are they at the same end, opposite ends, or on adjacent sides? • Imagine the air path inside the cylinder during scavenging: does it move straight through, cross from one side to the other, form a loop, or go up and then back down? • Compare that observed flow pattern with the textbook definitions of cross‑flow, loop, uniflow, and return‑flow scavenging. Which matches best?

✅ Before You Answer

• Verify which components in the drawing are labeled as scavenge air (usually colored and arrowed) and which are exhaust. • Confirm whether the exhaust outlet is at the top of the cylinder (valve in the head) or through ports in the liner near the bottom. • Before choosing, match the observed pattern to a simple description: air and exhaust at opposite ends (straight-through), air and exhaust on adjacent sides, air entering and turning back (return), or air looping around within the cylinder.