With the increasingly serious environmental pollution problem today, air filters have a very significant effect on protecting automotive engine systems. The main application function of this filter is to filter and process the air entering the engine cylinder, blocking some dust particles and other types of impurities outside the cylinder to prevent them from damaging the engine after entering, such as causing wear on the cylinder piston rings and reducing the service life of the cylinder. Air filters can be mainly classified into four types: T-type desert air filters with pre filtration function and oil bath air filters, as well as single stage air filters and double stage blade air filters without pre filtration function.

1. Analysis of the original intake resistance of the air filter assembly

In air filters, although single stage air filters do not have pre filtration function, this type of air filter has the smallest resistance to the original air intake, while double stage air filters with blade rings have slightly higher resistance, followed by oil bath air filters with pre filtration function. This type of filter already has a considerable resistance to the original air intake, But the biggest one is the desert air filter with a swirl tube, which has the greatest intake resistance to the raw air. Due to their different internal structures, different air filters have different resistance to the intake of raw air.

2. Analysis of the original filtration efficiency of the air filter assembly
The difference in the original filtration efficiency of air filters with different structures is very significant. However, the use of automotive air filters generally emphasizes the original filtration efficiency of the assembly. When analyzing the original filtration efficiency of an air filter assembly, the weight method is usually used for comparative analysis. However, this method often has limitations in its use. If the same two automotive filters have the same filtration efficiency of 99%, then the performance of these two filters cannot be further analyzed through the weight method. So using the weight method in this situation is clearly no longer meaningful. In this case, the original filtration performance of the air filter can be analyzed using the counting method. By counting the specific filtration quantity at each filtration stage, the performance of the air filter can be distinguished effectively.