Engineering · Diesel — Fuel
Heavy fuel oil (residual fuel) must be heated before injection mainly to:
- ARaise its cetane number
- BReduce its viscosity to the correct value for proper atomization✓ Correct
- CRemove its sulfur
- DPrevent it from igniting in the tank
Explanation
Residual fuel is too viscous to atomize cold. It is heated (often 120-150 C) to bring viscosity down to the injector's design range so it sprays and burns properly.
Authority: Diesel Engines (USCG engineering topic)
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