Dmetalmiki, you are misinformed, here maybe this will help you:
The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed. A slightly higher temperature, the fire point, is defined as the temperature at which the vapor continues to burn after being ignited. Neither of these parameters are related to the temperatures of the ignition source or of the burning liquid, which are much higher. The flash point is often used as one descriptive characteristic of liquid fuel, but it is also used to describe liquids that are not used intentionally as fuels.
Examples of fuel flash points
Petrol (gasoline) is designed for use in an engine which is driven by a spark. The fuel should be premixed with air within its flammable limits and heated above its flash point, then ignited by the spark plug. The fuel should not preignite in the hot engine. Therefore, gasoline is required to have a low flash point and a high autoignition temperature.
Diesel is designed for use in a high-compression engine. Air is compressed until it has been heated above the autoignition temperature of diesel; then the fuel is injected as a high-pressure spray, keeping the fuel-air mix within the flammable limits of diesel. There is no ignition source. Therefore, diesel is required to have a high flash point and a low autoignition temperature.
Petrol:
Flash point: > -43 °C (-45 °F [negative, below freezing point of water at +32 F])
Autoignition temperature: 246 °C (475 °F)
Diesel:
Flash point: >62 °C (143 °F)
Autoignition temperature: 210 °C (410 °F)
Jet Fuel:
Flash Point: >38 °C (100 °F)
Autoignition Temperature: 210 °C (410 °F)
Kerosene:
Flash point: >38-72 °C (100-162 °F)
Autoignition temperature: 220 °C (428 °F)
so diesel fuel ISN'T Flammable, it's combustable, big difference. You can take a rag soaked and burning with diesel fuel and put it out by rapidly stuffing it into a 5 gal bucket full of diesel...don't try that with gasoline which is flammable. the difference is the temp at which they will readily turn into a vapor which is ignitable when combined with air( think of spilling both diesel and gasoline(petrol) seperately on a cold day, the gas will evaporate much, much faster than the diesel. this is due to the low temp at which gasoline readily turns into a vapor.
The liquid fuel isn't actually burning, it's the vapor coming off the material. IIRC, to be considered flammable it has to readily form vapors below 100*F.
On a side note, Rudolph Diesel originally ran his diesels on peanut oil !!!!
this is why they also run on biodiesel ( think about the last time you saw a deep fat fryer on fire, they get super hot, but don't really burn unless you really screw up), vegetable oils, and other combustible but not flammable liquids.
also, there will be more residual from burning diesel due to all the additives... new mineral oil has to be a lot purer than standard diesel ( meaning diesel is allowed to have a lot more accidental things added to it, like water for one)
The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed. A slightly higher temperature, the fire point, is defined as the temperature at which the vapor continues to burn after being ignited. Neither of these parameters are related to the temperatures of the ignition source or of the burning liquid, which are much higher. The flash point is often used as one descriptive characteristic of liquid fuel, but it is also used to describe liquids that are not used intentionally as fuels.
Examples of fuel flash points
Petrol (gasoline) is designed for use in an engine which is driven by a spark. The fuel should be premixed with air within its flammable limits and heated above its flash point, then ignited by the spark plug. The fuel should not preignite in the hot engine. Therefore, gasoline is required to have a low flash point and a high autoignition temperature.
Diesel is designed for use in a high-compression engine. Air is compressed until it has been heated above the autoignition temperature of diesel; then the fuel is injected as a high-pressure spray, keeping the fuel-air mix within the flammable limits of diesel. There is no ignition source. Therefore, diesel is required to have a high flash point and a low autoignition temperature.
Petrol:
Flash point: > -43 °C (-45 °F [negative, below freezing point of water at +32 F])
Autoignition temperature: 246 °C (475 °F)
Diesel:
Flash point: >62 °C (143 °F)
Autoignition temperature: 210 °C (410 °F)
Jet Fuel:
Flash Point: >38 °C (100 °F)
Autoignition Temperature: 210 °C (410 °F)
Kerosene:
Flash point: >38-72 °C (100-162 °F)
Autoignition temperature: 220 °C (428 °F)
so diesel fuel ISN'T Flammable, it's combustable, big difference. You can take a rag soaked and burning with diesel fuel and put it out by rapidly stuffing it into a 5 gal bucket full of diesel...don't try that with gasoline which is flammable. the difference is the temp at which they will readily turn into a vapor which is ignitable when combined with air( think of spilling both diesel and gasoline(petrol) seperately on a cold day, the gas will evaporate much, much faster than the diesel. this is due to the low temp at which gasoline readily turns into a vapor.
The liquid fuel isn't actually burning, it's the vapor coming off the material. IIRC, to be considered flammable it has to readily form vapors below 100*F.
On a side note, Rudolph Diesel originally ran his diesels on peanut oil !!!!
this is why they also run on biodiesel ( think about the last time you saw a deep fat fryer on fire, they get super hot, but don't really burn unless you really screw up), vegetable oils, and other combustible but not flammable liquids.
also, there will be more residual from burning diesel due to all the additives... new mineral oil has to be a lot purer than standard diesel ( meaning diesel is allowed to have a lot more accidental things added to it, like water for one)