Study Of The Formation Of Dielectric Chains In Electrostatic Field

The electrostatic formation method is a kind of new method for porous ceramic preparation. The controlled formation of dielectric particles chains in electrostatic field is an important process of the porous ceramics preparation with the electrostatic formation method. We take the process of dielectric particles chains in electrostatic field as the main research object, and consider it theoretically. The potential distribution around the particles and the interaction force of the two particles during the particles chain formation will be analyzed. At the same time, the influence of the gas stream and the Van der Waals force between the particles should also be considered. The details of the thesis shown as follow:1. We will compare the present methods for analyzing the potential distribution around the particles and the interaction force of the two particles. The dipole approximation turned out to be too crude for closely spaced particles and the procedure using the bispherical coordinates require very complex calculation for the case of more the two particles. So we decide to use the re-expansion method.2. Using the re-expansion method, the potential distribution around the particles will be calculated for the case of two different spherical dielectric particles and the particles chain of the same spherical dielectric particles. The expression will be got.3. We got the graphs by using the Maxwell software, which show the potential distribution of dielectric particles in the electrostatic field. From the graphs, we can get the property of the potential distribution.4. We will use the equivalent multipole method to calculate the interaction electrostatic force for a single chain of particles aligned parallel to a uniformly applied electric field base on the expression of the potential distribution. Then the property of the force will be known.5. The influence of the gas stream will be considered. Then we will make sure which force due to the gas stream will influence the particles chain formation in the he electrostatic formation method.6. The powder particles and the gas stream is seen as the two-phase flow, and the powder particles is seen as the false fluid. We will get the differential eguation of particles group by analyzing the movement of them.7. The influence of the Van der Waals force between the particles will be considered. By the theoretical calculation, we can estimate the possible magnitude of the Van der Waals force between the particles.