Composite cooling performance of a rotating turbine blade cooling structure was investigated through heat transfer simulation with three-dimensional fluid-solid coupling
and the effects of radiation heat transfer and rotational speed on overall cooling effectiveness were discussed. Results showed that a local high-temperature area around the blade hub and hence a large scope of low cooling effectiveness occurred
leading to a nonuniform distribution of overall temperature for blade structure 1. The cooling effectiveness adjacent to the leading edge was improved
lessening the low effectiveness area as a result of more reasonable film flow distribution of blade structure 2. The cooling effectiveness on blade suction side was markedly enhanced through internal serpentine passages and a uniform distribution of integral cooling effectiveness was obtained for blade structure 3. The blade temperature increased with a regional temperature increment over 50K for the surface emissivity of 1
while the effect of radiation heat transfer cant be ignored. The overall cooling effectiveness on pressure side improved with the augmentation of rotational speed
resulting in a highest regional increase percentage of 15.6%
13.4% and 16.4% for the three structures
respectively. Nevertheless
the cooling effectiveness on suction side produced little change except a reduction at mid-chord region with the increase of rotational speed.