Explain the following properties i) Pour point ii) Viscosity iii) Ignition quality iv) Fire point

Explain the following properties i) Pour point ii) Viscosity iii) Ignition quality iv) Fire point
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1 Answer

Answer :

i. Pour point: Pour point is the temperature below which the entire mass of fuel, solid or liquid together, freeze and thus cause flow of fuel impossible. Pour point is usually 5 to 10 °C below the cloud point.

ii. Viscosity: Viscosity of a fuel is a measure of its resistance to flow.

iii. Ignition quality: The ability of a fuel to ignite when it is injected into the compressed-air charge in a diesel cylinder. It is measured by an index called the cetane number

iv) Fire point: Fire point is the temperature at which the flash will sustain itself as a steady flame for at least five seconds.
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