Can Raoult's Law Determine Boiling Points of Fuel Oil?

[hartmais]

Fuel oil like heavy fuel oil consists of multiple different Carbon and Hydrogen molecule strains. This means that there are a multiple of different boiling points with in the same oil. Cavitation in pumps and valves happen when due to the acceleration of the fluid the pressure drop causing the pressure of the fluid to fall below the boiling point. The bubbles that form then collapse at the point where the pressure then exceeds the boiling point causing damage to the pumps or valves. When working with homogeneous fluids like water it is relatively easy to calculate whether cavitation would occur since there are vapor tables available etc.

I know that there is also multiple grades of oil. I am interested at finding a pressure vs temperature curve where there would be some form of boiling that can cause cavitation in heavy fuel oil. In heavy fuel oil their are a small amount of diesel that is used to control the viscosity.

Though diesel is also a combination of a lot of different carbon hydrogen chains, I would have thought there would be some information available at the point where "First boil" would take place. The term "First boil" is my own for where enough of the carbon strains would boil out the oil to cause a notable increase in fluid volume.

Could some one please help with more information?

 

[Chestermiller]

Are you familiar with Raoult's Law?

 

[hartmais]

Thanks. I have read about Raoult's law and it makes sense. The problem I have is that I often here cavitation on fuel oil pumps and see the damage of the cavitation. Example If we are pumping heavy fuel oil with flash point of 60 degree C but say the temperature is 85 degree C we experience cavitation. The boiling temperature of the oil is however indicated as between 300 and 500 degree C.

My real question is how can I find a pressure vs temperature characterization that will indicate the cavitation potential of the oil.

 

[Chestermiller]

Just use Raoult's law to calculate the equilibrium pressure as a function of temperature for a solution of the given composition. Do not modify the composition.