Ceramic Matrix Composites (CMC) are a promising material because the allowable temperature is 200°C higher than that of conventional Ni-based super-alloys. Many attempts to apply this ceramic to hot section components of advanced gas turbine engines have been made. However, in order to fully gain the performance benefits from this advanced material, more understanding and advancement is needed. One item is to confirm the cooling performance of cooled CMC components like turbine nozzles. For conventional cooled nozzles, internal and external cooling is used. This paper presents two kinds of cooling performance tests with CMC turbine nozzles: one with only impingement cooling and the other with both impingement and film cooling. First, the impingement cooling test of CMC nozzle was conducted in the steady hot mainflow, with room temperature coolant in order to investigate the internal cooling performance of the nozzle. The impingement cooling Reynolds number was set at 1 × 10~4, which is consistent with that of actual gas turbine engines. The exit Mach number of the cascade was set at 1 approximately. Second, the test with both impingement and film cooling of the CMC nozzle was conducted. The film cooling was designed with its impingement cooling Reynolds number being equal to that in the impingement cooling performance test. The experimental results are presented and discussed in detail in this paper.
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