Ceramic parts such as a combustor of gas turbine requires the design considering strength reliability, because ceramics are easily fractured by thermal stress due to rapid changes of temperature. Therefore, it is essential to estimate the thermal shock stress and is also necessary to control the cooling rate of ceramic parts. In this paper, the thermal stresses at trip and steady state in a ceramic combustor liner are analyzed numerically by using a simple ceramic cylinder model, which is heated from the inside and is cooled from the outside. The propability of failure of a ceramic cylinder subjected to thermal stresses both at trip and steady state is also analyzed theoretically. As a result, the thermal shock stress at trip decreases with the increase in cooling rate at steady state. However, because the thermal stress at steady state increases with the increase in cooling rate, the cooling rate at steady state should be optimized to minimize the propability of failure in the ceramic cylinder system, considering the thickness of cylinder.

抄録全体を表示