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We developed a stinger-shaped injector (stinger injector) for supersonic combustors in cold-flow experiments. The stinger injector has a port geometry with a sharp leading edge in front of a streamwise slit. This injector produced higher jet penetration at a lower jet-tocrossflow momentum flux ratio (J) than a conventional circular injector. We applied the injector in a Mach 2.44 combustion test at a stagnation temperature of 2060 K. At a low fuel equivalence ratio (Φ) regime (i.e., low J regime), the injector produced 10% higher pressure thrust than the circular injector because of high jet penetration as expected from the coldflow experiments. Even at a moderate Φ regime, the stinger injector produced higher pressure thrust than the circular injector. At moderate Φ, the stinger injector held the flame around the injector and generated a precombustion shock wave in front of the injector. The presence of the precombustion shock wave decreased the momentum flux of the crossflow air and diminished the advantage of the injector for jet penetration. The injector, however, produced higher pressure thrust because better flame-holding produced higher pressure around the injector. At a higher Φ regime, the precombustion shock wave went upstream with both injectors. The far-upstream presence of a precombustion shock wave increased the

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When designing a combustor, numerical analysis should be used to effectively predict different performances, such as flame temperature, emission, and combustion stability. However, even with the use of numerical analysis, several problems cannot be solved by investigating single combustors because, in an actual engine, interactions occur between multiple combustors. Therefore, to evaluate the detailed phenomenon in an actual combustor, the interactions between all combustors should be considered in any numerical analysis. On the other hand, a huge amount of computational cost is required for this type of analysis. Here a large-eddy simulation employing a flamelet/progress variable approach is applied to the numerical analysis of industrial combustors. The combustor used for this study is the L30A from Kawasaki Heavy Industries, Ltd. Computations are conducted with a supercomputer (referred to as the “K-computer”) in the RIKEN Advanced Institute for Computational Science. All combustors in the L30A engine (from the compressor outlet to the turbine inlet) are simulated, including the fuel manifold. This engine has eight can combustors that are connected through the fuel manifold and compressed air housing unit. The total number of elements is approximately 140 million. The flow patterns for each combustor are similar in all cans. A swirling flow from the main burner is formed and accelerated by the supplemental burner. There is a high-temperature region before the supplemental burner. The flow field and temperature distribution in an actual combustor interacting with other combustor cans are simulated adequately. The mass flow rate of the air and those of the fuels are distributed equally for each can. Therefore, the outlet temperature difference for each can is also very small.

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