## 4 Results and Discussion
### Dynamic Response of Electric Field and Drag Force in the Separation Region  
In order to further analyze the effect of separation between atmospheric PM under the combined action of electric field and drag force. The commonly used anode corona voltage E is 30 kV, and the acceleration voltage E is 30 kV in the acceleration room to accelerate atmospheric particulate matter. Figure 12 describes the displacement response of PM\({}_{2.5}\) under different drag coefficients and electric fields. Figure 13 depicts the displacement response of PM\({}_{50}\) under different drag coefficients and electric fields. It can be seen  
In order to deeply analyze the influence of the drag coefficient and electric field intensity on atmospheric particulate matter, we further study the influence of drag coefficient and electric field intensity on atmospheric particle displacement with particle diameter. Figure 14 shows the variation of the displacement of PM\({}_{2.5}\) under different drag coefficients and electric field strength combinations. It can be seen from the figure that with the decrease of the electric field intensity E2, atmospheric particulate matter slowly changes from positive displacement to negative displacement, and the larger the particle diameter, the more obvious the effect. As the drag coefficient decreases, the displacement of atmospheric particles is greater in both the X and Y directions. Comparing (a) and (b) in Figure 14, when E2 is 433 V, PM\({}_{2.5}\) moves upward, and PM\({}_{10}\) basically keeps moving in the X direction. When the voltage rises, PM\({}_{10}\) starts to move upward, and PM\({}_{2.5}\) still moves upward. When the voltage drops to 43 V, PM\({}_{2.5}\) basically has no longitudinal displacement, and PM\({}_{10}\) moves downward. It can be seen that E2 is a suitable separation voltage of 433 V, and reducing the drag coefficient will improve the separation effect between atmospheric particles. Figure 12: Dynamic displacement response of PM\({}_{2.5}\) under the combined action of drag force and electric field: (**a**) \(X\)-axis displacement; (**b**) \(Y\)-axis displacement. Figure 13: Dynamic displacement response of PM\({}_{50}\) under the combined action of drag and electric field: (**a**) \(X\)-axis displacement; (**b**) \(Y\)-axis displacement. In order to further analyze the specific separation effect of atmospheric particles in space, under the same composite electric field and drag coefficient, the specific displacement changes of typical atmospheric particles PM\({}_{2.5}\), PM\({}_{10}\), and PM\({}_{100}\) are analyzed. By comparing (a) and (b) in Figure 15, it can be seen that when E2 is 433 V, PM\({}_{2.5}\) moves upward, PM\({}_{10}\) maintains lateral displacement, and PM\({}_{100}\) moves downward, which has an excellent separation effect, and subsequent easy collection of atmospheric particulate matter. When the voltage E2 is increased, PM\({}_{10}\) starts to move upward, and there is also a certain displacement law. When the drag coefficient is \(10^{-7}\), E1 is 433 V, and E2 is 433 V, the separation effect of atmospheric particles is more satisfactory. The smaller the drag coefficient, the better the separation effect of atmospheric particles. According to the suggested method, a particle separator is simulated by commercial software and then a three-dimensional model is established. The separation system mainly includes three customized charging rooms, acceleration rooms, and separation rooms. They require machining accuracy to be less than 2.5 um. The separation system also includes blowers, high-voltage negative pulse power supplies, electronic balances, flow meters, etc. The preliminary estimate is estimated to cost $72,000. The separation system is simulated and analyzed according to actual materials. The aluminum parallel metal plate is used as the electrode plate and filled with air to simulate the real environment. Mesh electrodes are used in the separation room to control the size of the electric field.