🔍 Key Concepts

• Lube oil temperature control methods in closed-loop systems • Role of a thermostatic valve versus a cooler alone • Difference between heat generation in bearings and active temperature regulation

💭 Think About

• Which component in a lube oil system can actively adjust flow path or flow rate in response to temperature changes? • Do the bearings or seawater actually "control" temperature, or do they just influence how much heat is added/removed? • Think about what must happen to the oil flow when it is too cold versus when it is too hot after the cooler.

✅ Before You Answer

• Identify which option involves an automatic control device that reacts directly to oil temperature. • Eliminate any choices that only describe operating conditions (speed, seawater temperature, heat carried away) rather than a specific regulating mechanism. • Confirm which option changes the proportion of oil through vs. around the cooler to maintain a set outlet temperature.