Which of the air intake systems listed will...

🔍 Key Concepts

• Specific fuel consumption (SFC) – what does “lower” SFC mean in terms of fuel burned per unit power? • How turbochargers and blowers use exhaust or mechanical energy to increase air supply to the engine. • The difference between devices that recover waste energy vs those that consume crankshaft power to drive them.

💭 Think About

• First, recall which devices are driven by the engine crankshaft and which are driven by exhaust gas; how does that affect overall efficiency and fuel per horsepower produced? • Think about which system allows more complete combustion with less additional load on the engine itself. • For each choice, ask: Does this method of getting more air into the engine cost extra engine power, or does it mainly use energy that would otherwise be wasted? How would that impact SFC?

✅ Before You Answer

• Be clear that lower specific fuel consumption means less fuel per unit of power (e.g., g/kWh or lb/hp·hr). • Identify which of the listed systems uses exhaust gas energy instead of taking power directly from the crankshaft. • Confirm which systems (Roots blower, piston blower) are mechanically driven and therefore impose a parasitic load on the engine.

Which of the air intake systems listed will result in the lowest specific fuel consumption?

Natural aspiration

Turbocharged

Roots blower

Piston blower

🔍 Key Concepts

💭 Think About

✅ Before You Answer