Views:0 Author:Site Editor Publish Time: 2021-08-23 Origin:Site
Air filtration principle
Dust and filter media adhesion: dust particles in the air, or doing inertial motion with gas flow, or move without regular motion, or moved by a certain field force, when the particles in the motion hit the obstacle, particles Van der Walsi between the obstacles make them stick together.
Filtration dielectric material: can effectively intercept the dust particles, and do not form excessive resistance to airflow. Messy interleaved fibers form a number of barriers to the particles, and the spatial space between fibers allows the airflow to pass smoothly.
Currently used materials have glass fibers, polypropylene fibers, polyester synthetic fibers, meltblown nonwovens, and the like. According to the movement law of the filter medium with the dust, the common filtering mechanism is divided into inertial principles, proliferation principle, and electrostatic principle.
Large particles are inertial in the airflow. The airflow disguise, the dust from the inertia deviates from the airflow direction and hits the obstacle. The greater the particles, the stronger the inertia, the larger the impact obstacle, the better the filtering effect. Small particle dust does not have a regular brown movement. The smaller the dust, the more violent movements, the more the opportunity to hit the obstacle, the better the filtering effect.
Small particle dust in the air is mainly browning. The smaller the particles, the higher the efficiency of the filter; the large particle dust is mainly treated, the greater the particles, the higher the efficiency of the filter. Partial dust is difficult to filter, and the filter performance is derived from the performance value of filtering efficiency. If the filter material is static or dust with static electricity, the filtration effect can be significantly improved. The main reason has two: electrostatic electric dust changes the movement trajectory and hits the obstacle; static power makes dust more firm on the medium.
Filter resistance: The captured dust produces additional resistance to the airflow, and the resistance of the filter in use will gradually increase. The captured dust is integrated with the filtration medium to form an additional obstacle, so the filtering efficiency of the filter in use will increase. Most of the captured dust is gathered on the winding surface of the filter material. The larger the filter material, the more dust can be accommodated, the longer the life of the filter.
The more dust on the filter material, the greater the resistance. When the resistance is too unreasonable, the filter is scrapped. Sometimes, excessive resistance will make the dust scattered on the filter, and when this hazard occurs, the filter should also be replaced in time. The filter resistance increases with gas flow, by increasing the area of the filter material, the relative wind speed passing through the filter material can be reduced to reduce the filter resistance.
新Air filterThe resistance is called \"initial resistance \", the resistance value of the air filter is scrapped\"\" final resistance \". When designing, there is a representative resistance value, which is called \"design resistance \", the general method is the average of the initial resistance and final resistance. In most cases, the final resistance of the air filter is generally 2-4 times the initial resistance. The filter reaches the final resistance, meaning that the filter is replaced.