A series of large-scale parallel simulations of flat-plate film cooling are performed to uncover the qualitative and quantitative relationship between coherent structure dynamics and heat-transfer features. The near-wall flow dynamics and heat-transfer features at five inclination angles of and are also analyzed in detail. Hybrid thermal lattice Boltzmann method and multiple graphic processing units are used to fulfill the simulation efficiently. The detailed coherent structure dynamics are captured by the high-resolution simulation. The results show that large vertical size of coherent structure and great intensity of negative spanwise vorticity indicate prominent coolant-jet detachment leading to bad cooling performance. Meanwhile, the value of area-averaged film cooling effectiveness is proportional to 4th power of area-averaged non-dimensional turbulent kinetic energy. This quantitative relationship is first proposed to make further understanding of film-cooing mixing mechanism. On the other hand, inclination angle has a complicated impact on flow dynamics and heat-transfer features. The vertical size of coherent structure becomes large and the strength of negative spanwise vorticity is strengthened in the case of large inclination angle, resulting in poor cooling performance. The influence of inclination angle is less remarkable in large-inclination-angle case than that of small inclination angle.
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