Investigation on hybrid thermal features of aero- engines from combustor to turbine

The thermal interplay between the combustor and the turbine exerts remarkable effects on the performance of an aero-engine. The non-uniform distributions of the temperature and thermal radiation exist at the combustor outlet due to the operation characteristics of combustor and turbine. These uneven thermal features may cause hot spots on the blade surface, and even lead to material damage in regions such as the blade tip. Generally, the combustor and the turbine were separately treated and the thermal interconnection of each other were seldom involved except for the predesigned inlet conditions, which cannot be completely consistent with the actual turbine inlet conditions. To resolve such a problem, the present study proposes an integrated numerical simulation approach on the combustor-guide vane-rotating blade combined structure operating at engine-representative parameters (pressure ratios, temperature, Mach number and so on) with taking the effect of thermal radiation into account. The detailed analysis reveals that the distributions of temperature distributions of turbine inlet are closely related to the combustion gas swirl flow, dilution hole injection flow and combustor liner cooling air. The secondary flow at the combustor exit increases the mixing of the cold fluid and the hot streaks (HS) and reduces the temperature unevenness of the rotor blades. This elaborate investigation provides a deeper insight into the complex aero-thermal physics in turbine passage relevant to the aero-engine design and analysis.