An experimental and numerical study of flow and heat transfer in cooling channels with pin fin-dimple and pin fin-groove arrays

Authors

Vladimir Kindra - National Research University "Moscow Power Engineering Institute"
Sergey Osipov - National Research University "Moscow Power Engineering Institute"
Daria Kharlamova - National Research University "Moscow Power Engineering Institute"
Igor Shevchenko - National Research University "Moscow Power Engineering Institute"

Abstract

The study aims at improving the cooling design for the gas turbine components. A numerical and experimental study was conducted to investigate the heat transfer and the flow friction performance in rectangular channels with staggered arrays of pin fins, pin fin-dimples, where dimples located under the pin fins and pin fin-grooves, where the rows of pin fins located in grooves. The comparison based on the experimental data in the Reynolds number range of 4000–14000 showed that, compared with pin fin channel, the pin fin-dimple channel has increased convective heat transfer performance by about 11% and increased flow friction by 9%, the pin fin-groove channel has increased convective heat transfer performance by about 36% and decreased flow friction by 46%. In addition, numerical computations have been done to investigate the physical details about the flow and heat transfer in the pin fin-dimple and pin fin-groove channels. The computations showed that the dimples and grooves increase the near-wall turbulent mixing level by producing strong vortex flows around pin fins, and therefore enhance the convective heat transfer in the channel.