Premkumar, K2017-08-102023-10-192017-08-102023-10-192016ROLL NO.126107013https://gyan.iitg.ac.in/handle/123456789/820Supervisor: Rajesh Kumar UpdhayayGas – solid Circulating fluidized bed (CFB) finds application in industrial process like cracking, combustion, gasification, drying, etc. The major reasons cited being operation flexibility, efficiency, short residence time, etc. Even though, CFB is in use for more than three decades, fundamental understanding is still insufficient. Design and scale up of CFB is still empirical and based on experience rather than science. This is mainly due to the complexity of gas – solid, solid – solid and solid-wall interactions. Multi-scale nature of these interactions, both in length and time scale, makes it more difficult to delineate the hydrodynamics. These interactions are also a function of geometry and scale, which makes scale-up of CFB more challenging. Numerical simulation is cost effective approach however, has been largely suffering from lack of experimental data. Further, most of the studies on scale effect are limited to the mean values. Very few studies are available on the fluctuations at different scales. Further no study is available on scale study using noninvasive techniques and also unbiased with scale.enCHEMICAL ENGINEERINGThesis