| dc.description.abstract | In industry and life, storage tank usually plays an important part of storing or discharging the particles when we needed. Some factors will affect storage tank discharging situation, such as the outlet size of silo, particle’s thickness and the internal flow field. Under certain conditions, storage tank will appear arch to stop discharging which is an annoying issue for general industry or people’s livelihood.
This research was built a two-dimensional silo adding a clockwise rotation obstacle into the silo, also using electronic controller to change obstacle speed and open the outlet by air compressor. Filling fixed weight particles and captured particle’s photographs to analyze data with high speed camera and PTV (Particle Tracking Velocimetry) code. The flow rate, velocity field, packing fraction with changing rotation speed and compared arching formation, destruction ability will be discussed in the end.
After a series of experiments, it is found that rotating obstacle will affect the discharging physical quantities and the trends will be changed by different obstacle’s height. At higher positions, the obstacle is not easy to affect discharge but when obstacle height reduced, it will cause velocity change which make the degree of collision increase. Silo’s discharging situation will be different and changed by particle collision. When the obstacle reaches a too low position, the effect of discharging is most obvious because it is closest to the outlet than the other heights also the arch formed at this position is different. In the process of increasing the speed, it can be seen tendency of damage or produce the arch and can be matched with the shear rate to fit a linear relationship and make predictions in the future. | en_US |