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Comparisons of Heat Transfer Enhancement of an Internal Blade Tip with Metal or Insulating Pins

Xie, Gongnan LU and Sundén, Bengt LU (2011) In Advances in Applied Mathematics and Mechanics 3(3). p.297-309
Abstract
Cooling methods are needed for turbine blade tips to ensure a long durability and safe operation. A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the three-dimensional turning effect and impingement like flow. Improved internal convective cooling is therefore required to increase the blade tip lifetime. In the present study, augmented heat transfer of an internal blade tip with pin-fin arrays has been investigated numerically using a conjugate heat transfer method. The computational domain includes the fluid region and the solid pins as well as the tip regions. Turbulent convective heat transfer between the fluid and pins, and heat conduction within pins and tip are... (More)
Cooling methods are needed for turbine blade tips to ensure a long durability and safe operation. A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the three-dimensional turning effect and impingement like flow. Improved internal convective cooling is therefore required to increase the blade tip lifetime. In the present study, augmented heat transfer of an internal blade tip with pin-fin arrays has been investigated numerically using a conjugate heat transfer method. The computational domain includes the fluid region and the solid pins as well as the tip regions. Turbulent convective heat transfer between the fluid and pins, and heat conduction within pins and tip are simultaneously computed. The main objective of the present study is to observe the effect of the pin material on heat transfer enhancement of the pin-finned tips. It is found that due to the combination of turning, impingement and pin-fin crossflow, the heat transfer coefficient of a pin-finned tip is a factor of 2.9 higher than that of a smooth tip at the cost of an increased pressure drop by less than 10%. The usage of metal pins can reduce the tip temperature effectively and thereby remove the heat load from the tip. Also, it is found that the tip heat transfer is enhanced even by using insulating pins having low thermal conductivity at low Reynolds numbers. The comparisons of overall performances are also included. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Heat transfer enhancement, tip-wall, pins, thermal conductivity, weight
in
Advances in Applied Mathematics and Mechanics
volume
3
issue
3
pages
297 - 309
publisher
Global Science Press
external identifiers
  • wos:000294090000003
  • scopus:84867615548
ISSN
2070-0733
DOI
10.4208/aamm.10-10s2-03
language
English
LU publication?
yes
id
cde6d13d-b6ac-468b-957e-c75ca51337b7 (old id 2162261)
date added to LUP
2011-09-21 08:49:23
date last changed
2017-08-13 03:03:37
@article{cde6d13d-b6ac-468b-957e-c75ca51337b7,
  abstract     = {Cooling methods are needed for turbine blade tips to ensure a long durability and safe operation. A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the three-dimensional turning effect and impingement like flow. Improved internal convective cooling is therefore required to increase the blade tip lifetime. In the present study, augmented heat transfer of an internal blade tip with pin-fin arrays has been investigated numerically using a conjugate heat transfer method. The computational domain includes the fluid region and the solid pins as well as the tip regions. Turbulent convective heat transfer between the fluid and pins, and heat conduction within pins and tip are simultaneously computed. The main objective of the present study is to observe the effect of the pin material on heat transfer enhancement of the pin-finned tips. It is found that due to the combination of turning, impingement and pin-fin crossflow, the heat transfer coefficient of a pin-finned tip is a factor of 2.9 higher than that of a smooth tip at the cost of an increased pressure drop by less than 10%. The usage of metal pins can reduce the tip temperature effectively and thereby remove the heat load from the tip. Also, it is found that the tip heat transfer is enhanced even by using insulating pins having low thermal conductivity at low Reynolds numbers. The comparisons of overall performances are also included.},
  author       = {Xie, Gongnan and Sundén, Bengt},
  issn         = {2070-0733},
  keyword      = {Heat transfer enhancement,tip-wall,pins,thermal conductivity,weight},
  language     = {eng},
  number       = {3},
  pages        = {297--309},
  publisher    = {Global Science Press},
  series       = {Advances in Applied Mathematics and Mechanics},
  title        = {Comparisons of Heat Transfer Enhancement of an Internal Blade Tip with Metal or Insulating Pins},
  url          = {http://dx.doi.org/10.4208/aamm.10-10s2-03},
  volume       = {3},
  year         = {2011},
}