Influence of slotted inclination angle on velocity characteristics in fluidization systems via computational fluid dynamics analysis

Fluidization is the process in which solid particles are suspended in a fluid-like state and widely used in power generation, chemical process, mineral processing industries, drying process and etc. These studies are carried out due to the constraints on conventional fluidization system which can inferred to; (i) Several type of distributor designs, which can influence the bubble size and lowers the fluidization performance, (ii) The conventional fluidization systems does not fluidize at one specific value thus directly affecting the bed behavior, and (iii) The pressure drop in conventional fluidization is not constant with increasing air velocity; affecting bed weight or bed moisture content. Therefore, the current study aims to; (i) Ability to assess the operational range of several types of distributor that focus on slotted inclination angle and slotted number of perforated plate distributor, (ii) Ability to verify the velocity component on airflow distribution of a current perforated plate distributor design, and (iii) Ability to evaluate the optimum geometry of perforated plate distributor via optimisation method that focuses on low pressure drop, uniform velocity and high tangential velocity. In order to achieve the goal outlined, several methods have been proposed in these studies. Firstly, the numerical simulation of Computational Fluid Dynamics (CFD) was used to investigate the parameters that can influence the perforated plate distributor with varying slot numbers (10, 12 and 14) and at various slotted inclination angles (15°, 45° and 90°). Secondly, the CFD is used to investigate the velocity characteristics of each velocity component such as velocity magnitude, tangential velocity, axial velocity and radial velocity as well as the pressure drop effected by slotted distributor configuration. And thirdly, the extracted data was evaluated by using statistical analysis on mean values, standard deviation, and also using an optimisation method like Full Factorial Design (FFD). It has been observed that the most significant findings in this study which represent the optimum design of a perforated plate distributor in a fluidization system were 45° angled slot inclination and 10 slots number respectively. This optimum design has formed a velocity uniformity with a higher tangential velocity of 24.39 m/s with a low standard deviation of 3.7% and a lower pressure drop of 2817.24 Pa, respectively. Moreover, extended analysis via optimisation method using ANOVA has shown that slotted inclination angle has significant parameter on the values of mean tangential velocity and pressure drop. Based on the ANOVA results, pressure drop is the most significant contributing parameter in lessening energy consumption on the fluidization systems.