🔍 Key Concepts

• Turbocharged diesel engine under constant speed governor – what changes when you put more load on the shaft? • Relationship between load and exhaust temperature, air (scavenge/air box) pressure, and mean effective pressure (MEP) • How the fuel rack/governor responds to increased load to maintain RPM

💭 Think About

• When the propeller or generator takes more power from the engine, what must happen to fuel injection to keep RPM constant? How does that affect combustion temperature and exhaust gas? • If more fuel is burned per cycle, what happens to the pressure of the air being supplied by the turbocharger into the cylinders/air box? Does the turbo have to do more work? • How is mean effective pressure (MEP) related to engine load and brake power? When load increases at the same speed, does MEP go up, down, or stay the same?

✅ Before You Answer

• Verify which parameters (exhaust temperature, air box pressure, MEP) are known indicators that engine load has increased on a turbocharged diesel at constant RPM. • Check that you understand the role of the governor: it keeps speed nearly constant by adjusting fuel, which in turn affects cylinder pressure and exhaust energy. • Consider whether any one of the listed quantities could realistically decrease when load increases, and eliminate that choice. Then see if more than one of them must increase together.