What method is used to supply air to the...

🔍 Key Concepts

• Trace the airflow path from the air intake through the turbocharger and into the scavenge air receiver/air box in the illustration. • Think about what happens at low load vs. full load on a large 2‑stroke diesel and when an auxiliary blower is normally needed. • Consider whether the piston in a crosshead 2‑stroke actually pumps fresh air into the cylinder, or if it mainly uncovers scavenge and exhaust ports.

💭 Think About

• Follow the arrows and ducting in the drawing: where does air first enter, what machine compresses it, and where does it collect before entering the cylinder? • At very low engine speed, is there enough exhaust energy to drive the turbocharger effectively, or is another device used to maintain sufficient scavenge air? • Look closely at the piston and liner: does the piston have any separate intake-pumping space (like a crankcase pump), or is air supplied from an external charging system?

✅ Before You Answer

• Identify the component labeled at the top of the drawing that resembles a turbocharger compressor and note when it is effective. • Look for any auxiliary blower or motor-driven blower connected to the scavenge receiver and think about when it would operate. • Verify from the illustration whether there is any crankcase-compression or pumping space below the piston that would draw in and push out intake air, or if all air comes from pressurized scavenge air.

What method is used to supply air to the cylinders of the diesel engine illustrated? See illustration MO-0003.

Operation of the turbocharger at full load

Operation of an auxiliary blower at low load

The pumping action of the piston

All of the above are correct.

🔍 Key Concepts

💭 Think About

✅ Before You Answer