%0 Journal Article %A Luo, Lei %A Wang, Chenglong %A Wang, Lei %A Sunden, Bengt %A Wang, Songtao %D 2017 %I Begell House %K Lamilloy, pin fin, heat transfer, friction factor, cone-shaped %N 7 %P 657-679 %R 10.1615/HeatTransRes.2016013575 %T EFFECTS OF PIN FIN CONFIGURATIONS ON HEAT TRANSFER AND FRICTION FACTOR IN AN IMPROVED LAMILLOY COOLING STRUCTURE %U https://www.dl.begellhouse.com/journals/46784ef93dddff27,1d78c2331ed2dd15,3d2dab4b58751c2e.html %V 48 %X In this study, numerical simulations are conducted to investigate the effects of pin fin location, pin fin diameter, and pin fin shape on the target and pin fin surfaces heat transfer as well as friction factor in an improved Lamilloy cooling structure. The pin fin normalized location is varied from 0.35 to 0.65 while the pin fin diameter is changing from 15 mm to 60 mm. Cone-shaped pin fins are introduced, and the root to roof diameter ratio of the cone-shaped pin fin is ranging from 0.5 to 2. The Reynolds number is between 10,000 and 50,000. Results of the target and pin fin surfaces Nu number, friction factor, and flow structures are included. For convenience of comparison, the Lamilloy cooling structure whose pin fin normalized location is 0.5 with a pin fin diameter of 30 mm is studied as the baseline. It was found that with increase of the pin fin normalized location, the heat transfer on the pin fin surfaces is gradually decreased while the friction factor shows a lower value as the pin fins are positioned either near the impingement center or the film holes. This trend is also found for increasing the pin fin diameter. In addition, the heat transfer on the pin fin surface is increased remarkably by using a cone-shaped pin fin with a slight target surface heat transfer penalty. It was also found that by changing the pin fin location, pin fin diameter, and the pin fin shape, it may reach 7.6% higher values than the baseline thermal performance based on the target surface Nu number while it is 43.58% based on the pin fin surface. %8 2017-06-21