Analysis of Temperature/Stress Distributions in a Hot Gas Tubular Ceramic Filter under Thermal Shock
Chunhong CHEN, Hideo AWAJI, Yasushi MATSUSHIMA, Satoshi KITAOKA and Fusayuki NANJO
Abstract:A thermal cyclic fatigue testing method for a hot gas tubular filter proposed by Matsushima, et al. simulates the stress state in the filter during reverse pulse cleaning by blowing air. The filter is composed of two layers, one is a thick inner layer made of silicon carbide with coarse pores and the other is a thin outer layer made of mullite with fine pores. In this paper, we presented a new technique for analyzing temperature distributions in a filter in cold blowing air on the assumption that a Biot number could express a heat loss inside the filter caused by blowing air. Temperature and stress distributions in the filter were analyzed numerically on condition that the filter was exposed to high temperature flue gas and received thermal shock by cyclic blowing air. Residual stresses after sintering were also analyzed. The results revealed that the stresses were greatly affected by the thickness of the mullite layer, there were considerable tensile residual stresses in the mullite layer, and the thicker layer of silicon carbide had higher thermal shock stresses on the inner surface of the filter. Key Words:Thermal cyclic fatigue, Ceramic filter, Bilayer cylinder, Silicon carbide, Mullite, Thermal stress, Residual stress