用离散颗粒数值模拟对陶瓷过滤器过滤特性的研究

A STUDY ON THE FILTRATION PERFORMANCE OF CERAMIC FILTER BY NUMERICAL SIMULATION

高温除尘是IGCC和PFBC-CC商业化的关键技术之一。陶瓷过滤器是最具发展潜力的除尘技术之一。该文以探讨高效的过滤途径为目的,通过数值模拟的方法,分析了不同的气流速度和不同的通道形状对陶瓷过滤器除尘效率的影响。模拟中,颗粒场采用离散颗粒运动模型,气相场采用格子Boltzmann方法。研究发现:如果粉尘颗粒偏大(相对于陶瓷过滤器空隙尺寸),可以通过增加陶瓷过滤器的厚度来提高过滤效率;如果粉尘颗粒很小,必须尽可能的降低气流速度才能达到高的除尘效率;在高气流速度下,增加陶瓷过滤器厚度对提高细小颗粒的过滤效率几乎不起作用。

Dust removal under high temperature is one of key problems for commercial IGCC and PFBC-CC. Ceramic Filter possesses itself of a great potentiality in development. Aiming at the high filtration efficiency approaches, the paper analyzed the effect of gas velocity and shape of channel on filter efficiency by numerical simulation. In the simulation, solid-field is simulated by a model of dispersing granules and gas-field is simulated by Lattice Boltzmann method. It is found that if the granule is large according to the size of ceramic filter interstice, the filter efficiency could be increased by thicker ceramic filter; if the granule is very small, high efficiency can be got only under as much as lower gas velocity; the thickness of ceramic filter can almost do nothing to filter efficiency in high gas velocity.