【摘要】 利用实验方法很难获得粉体内部气流轨迹和压力分布的详细信息,因此仿真技术是研究粉末压制的重要手段之一。针对粉体床内部在压制过程中的气体流场变化,采用基于双流体模型的二维多相流CFD软件Fluent对粉体床内的气流进行模拟。通过研究压制过程中初期、中期和末期3个时间点的气体体积分布和速度分布,发现压制速度是粉末压制非常重要的因素。由于粉床中的气体主要聚集在靠近压头的上层,因此提出在压头表面设计排气孔,有助于粉末中的空气流出,提高砖坯质量。更多还原

【Abstract】 It is difficult to obtain the detailed information of flow trajectory and pressure distribution in powder by experimental method, so the simulation technology is one of the important means to study powder compaction. Aiming at the change of gas flow field in the compaction process of the powder bed, the two-dimensional multiphase flow CFD software Fluent based on the two-fluid model was used to simulate the flow in the powder bed. By studying the gas volume distribution and velocity distribution at the three time points in the process of pressing, it is found that the pressing velocity is a very important factor in powder pressing.Since the gas in the powder bed is mainly concentrated on the upper layer near the pressure head, it is suggested that the design of air vent on the surface of the pressure head may help the air flow out of the powder and improve the quality of the brick.更多还原