What is the impact of excessive diesel flash point on combustion?

Flash point is one of the safety indicators of diesel fuel. The safety of diesel fuel during use and storage is expressed by its flash point. The lightning performance of diesel has almost nothing to do with the performance of diesel. It is only stipulated to ensure the safety when managing the use of diesel. It has little to do with the inherent combustibility.

Flash point refers to the lowest temperature at which a petroleum product is heated to the point where its vapor comes into contact with a flame to cause an instant flash fire under specified conditions. The lighter the oil, the lower the flash point. The hazard level of oils is classified based on their flash point. From the flash point, the composition of the oil can be judged and the fire hazard of the oil can be identified. The flash point measured with a closed flash point tester is called closed flash point and is generally used to measure light oil products. The higher the flash point, the safer it is. It has little to do with inflammability.

The flash point of diesel also represents its evaporability. A high flash point and evaporability are certainly not ideal. Does poor evaporability have little to do with combustion? How much should the flash point generally not exceed?

There is no impact at all. If it is winter, diesel with a low flash point may surprise you. . . It's so good to start a fire. . . but * * The lowest flash point indicator specified is 45. The reason why a flash point indicator is specified is for safety issues in use. . . If the flash point reaches 20 degrees, it will definitely be judged as unqualified according to the factory specifications. But when it is added to the fuel tank for use, there will not be any problems, because the diesel engine is compression ignition. It relies on the high-pressure compression of the pump to mix the high temperature with oxygen (air) and burn it. The flash point is low, which just allows the diesel to be ignited and burned in advance. . . :lol

The flash point is closely related to the distillation range and the initial distillation height, that is, the composition of diesel fuel. If the flash point is too high, it means that the initial distillation of diesel oil is higher and heavier. . . But once it burns, the calorific value may rise. The flash point has nothing to do with the result and process of combustion, but has more to do with the ignition of the diesel in the initial combustion stage. Flash point is a quantitative numerical index to evaluate the safe use of diesel fuel. . . :lol This post was last edited by wangsc on 2009-3-9 11:25 ]

How can you say that it has little to do with combustion? Diesel has a high flash point, and the combustion quality is poor when the diesel engine is used. The fuel starts to burn delayed, the combustion speed is slow, and the fuel cannot be completely burned. thus affecting the reduction of engine power~~~

Personally, I think that although the flash point of diesel is only one of the indicators for evaluating the safe use of diesel, an excessively high flash point itself does not affect the combustion performance of diesel. On the premise of ensuring that the other properties of the product are qualified, a high flash point is definitely a good thing. But it will also indirectly reflect other properties of diesel. If the flash point is too high and the proportion of heavy components in diesel increases, the relative viscosity of diesel will increase. At this time, you need to pay attention to see if the viscosity is qualified (it will mainly affect the fuel supply of diesel). ； The proportion of heavy components increases, the diesel becomes heavier, and the diesel process may fail (overweight diesel engines increase fuel consumption, increase wear, and reduce power) ； In addition, as the proportion of heavy components increases, the carbon residue value of the 10% diesel residue will also increase. At this time, it is necessary to see whether this indicator is exceeded (reflecting the thermal oxidation stability of the diesel, which is too high to cause carbon deposits in the nozzle and cylinder)

Diesel flash point is only one of the important indicators for evaluating the safe use of diesel. High flash point itself does not affect the combustion performance of diesel. A high flash point is a good thing for diesel use.

You have confused the flash point with the initial boiling point. "The delay in the start of burning of fuel" corresponds to the initial boiling point, and "the fuel cannot be completely burned" corresponds to the dry point.

In reply to Bai Ding's post on the 10th floor, the information I read said: Diesel has high autoignition point and flash point, poor combustion quality, delayed fuel combustion start time, slow combustion speed, and incomplete combustion of fuel. I read that right~~~~~~~~:)

The flash point of diesel is too high, which has a great impact on the combustion of the diesel engine and makes it difficult to start.

Thank you everyone for your replies. Although I didn't get a clear answer, I still benefited a lot from everyone's discussion.

The national standard stipulates that the flash point of diesel fuel should not be lower than 57 degrees, mainly for safety and combustion start-up considerations. Too high a flash point will make it difficult to start.

It's equivalent to less kerosene in diesel. harm: Cetane number emits black smoke

Excessive lightning can affect engine starting

Brother, is there any more diesel available?

There is a dry point, which is the temperature displayed by the thermometer at the moment when the last drop of liquid comes out.

Reply on the 5th floor: The flash point is low, it just allows the diesel to ignite and burn in advance. . . Does this sentence have the opposite meaning? A low flash point has a higher ignition point. How can it be possible to "start" the fire in advance? A high flash point means a high oil specific gravity, but the flash point is not a criterion for evaluating diesel combustion, but only a safety factor. Diesel mainly depends on the cetane number, and furthermore, the temperature at 50% of the distillation range.

It doesn't matter much, but if the flash point of diesel is too high, it will be difficult for the machine to ignite in winter. Generally, different diesel brands have different flash points. For example, the flash point of No. 10 diesel is definitely lower than the flash point of No. 0 diesel.