The effect of different rotational types on dynamics properties in a two-dimensional sheared granular flows.

• Main Authors: Wen-cheng Yu, 余文正
• Other Authors: Shu-san Hsiau
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/83616487807056556468

碩士 === 國立中央大學 === 機械工程研究所 === 99 === In fluid dynamics, liquid flow is continuous flow. In microcosmic, the relative displacement is not yet one characteristic length. In granular flow, the flow is not continuous flow, the weak attraction around particle will let relative placement over one characteristic length. In fluid dynamics, Navier-Stokes equation is usually used to describe the flow behaviors in tube flow, plate flow and draft flow. In granular flow, multiphase flow behaviors may exist as granular materials are driven by external force. Granular materials may behave solid, liquid and gas depending on the processing conditions. Thus, general theory is still poor to describe the granular flows due to the complex flow behavior. In this thesis, the two-dimensional annular shear cell is used to investigate the dynamic properties of granular flow with different rotational types. Through experiment analyze, we know the velocity profile is roughly exponential decay from shearing boundary with only inner wall or outer wall rotation. The tangential velocity of particles with rotating outer boundary is larger than rotating inner boundary under the same rotating tangential velocity. Pass by analyze, the results show that the local solid fraction is different near inner and outer shear boundary, particles collision violently when solid fraction is higher. In this thesis, we also discuss the flow behaviors by rotating both walls with the same direction rotation and inverse direction rotation.