Engineering · Diesel — Fuel
Heavy fuel oil is heated before injection primarily to:
- ARaise its flash point
- BLower its viscosity so it atomizes properly✓ Correct
- CIncrease its cetane number
- DRemove dissolved air
Explanation
Residual fuels are very viscous at ambient temperature. Heating reduces viscosity to the value needed for the fuel pump and injectors to atomize it into a fine, combustible spray.
Authority: Diesel Fuels (USCG engineering topic)
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