🔍 Key Concepts

• Sensible heat vs latent heat (what changes in each case) • What happens to steam when it condenses on a colder surface • What happens to the temperature and phase of heavy fuel oil during normal heating in a heat exchanger

💭 Think About

• When you heat heavy fuel oil in a heat exchanger, does its temperature change, its phase change, or both? Which type of heat is associated with that? • When steam is used as a heating medium and gives up energy to the fuel, is the steam typically condensing or just cooling as a gas? What type of heat transfer is associated with condensation? • Think about which fluid is changing state and which fluid is only changing temperature in this process.

✅ Before You Answer

• Verify which type of heat (sensible or latent) is linked to a change of temperature without phase change. • Verify which type of heat is linked to phase change at essentially constant temperature. • Identify which medium (steam or heavy fuel oil) is undergoing a phase change in this typical marine heat exchanger arrangement.