Injectors for use with heavy fuel oil may be...

🔍 Key Concepts

• Heavy fuel oil properties and how its viscosity and temperature affect combustion and injector operation • Purpose of cooling injector components that are in contact with very hot fuel and combustion gases • Effects of overheating at the injector nozzle tips (e.g., deposits, erosion, preignition)

💭 Think About

• Think about what actually happens to injector parts when very hot, viscous heavy fuel oil is used over long periods. Which problem would cooling directly reduce? • Which option describes a problem that typically occurs at the nozzle outlet exposed to combustion heat and hot fuel, rather than deep inside the system? • Consider which of the listed problems is most closely associated with overheating and deposit formation on fine passages and holes.

✅ Before You Answer

• Match each choice to a known injector problem: corrosion, delivery rate, preignition, or nozzle deposits, and ask which one is strongly heat‑related at the nozzle tips. • Ask yourself: is the main goal of internal cooling to improve performance/economy, or to protect precision parts from heat‑related damage and fouling? • Mentally picture the very small holes in an injector nozzle and what excessive heat plus heavy fuel would tend to do there over time.

Injectors for use with heavy fuel oil may be internally cooled by either water or light oil to __________.

prevent heat corrosion to internal components

increase fuel delivery rate and economy

prevent preignition

avoid carbonization of the nozzle tips

🔍 Key Concepts

💭 Think About

✅ Before You Answer