which takes both the fluid and solid domains into consideration
was utilized to investigate the effect of pressure side cutback geometry on the cooling performance in a typical gas turbine blade. In order to validate the present numerical methods
the computed film cooling coefficient and pressure were compared with the experimental data. After the reliability and accuracy of the numerical method have been demonstrated
the influence of blowing ratio and lip thickness on the cooling performance was studied in detail. It shows that
among the selected three standard k-ε turbulence model
k-ω turbulence model and SST k-ω turbulence model
the k-ω turbulence model has superior accuracy in predicting the cooling performance of the blade trailing edge cutback. The conjugate heat transfer method considering both fluid domain and solid domain could properly resolve the temperature distributions near the cutback lip. As the blowing ratio increases
the convection heat transfer in the blade cutback channel is enhanced
and the corresponding film cooling coefficients are increased at the cutback outlet. If the height of the ejection slot is fixed
the scale of the vortices at the slot exit is increased with the increase of lip thickness. Such flow pattern reduces the impact effect of mainstream to the trailing edge cutback
which leads to a slight improvement of the overall cooling effectiveness at the cutback outlet region. However
the loss coefficient of the whole flow region is inevitably increased.
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Keywords
references
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