Study on turbine blade overall cooling effectiveness under thermal radiation and non-uniform inlet temperature

Abstract

As the inlet temperature of the turbine continues to rise, if only heat conduction and convective heat transfer are considered, the temperature difference between numerical simulation and experimental will become apparent. The overall cooling effectiveness is generally used to evaluate the effect of cooling structures. However, the overall cooling effectiveness of turbine blades is difficult to measure directly due to the high temperature and pressure operating conditions. If the analogy method is established, the measurement of the overall cooling effectiveness of turbine blades under engine conditions can be carried out under experimental conditions. Therefore, it is important to study the analogy method of overall cooling effectiveness under thermal radiation. The analogy method of the overall cooling effectiveness under thermal radiation was established through one-dimensional coupled heat transfer analysis, which proposed to match the radiation term by Burger number and Boltzmann number. The matching characteristics under non-uniform inlet temperature were analyzed using numerical simulation. The results show that the method of matching the radiation term of overall cooling effectiveness is verified by numerical results. The effect of non-uniform inlet temperature on the overall cooling effectiveness matching is strongly correlated with temperature ratio, so the matching of temperature ratio should be prioritized.

Keywords

• Analogy principle
• Non-uniform inlet temperature
• Overall cooling effectiveness
• Turbine blade
• Thermal radiation