THERMAL SCIENCE

International Scientific Journal

HEAT TRANSFER ENHANCEMENT BY SINUSOIDAL WAVY TAPE INSERT IN TWO-PASS RIBBED CHANNELS

ABSTRACT
The turbine inlet temperature is one of the most critical parameter that determines the thermal efficiency and thrust-weight ratio of the gas turbine. However, the higher gas turbine inlet temperature significantly increases the thermal stress on the blade, which necessitates effective cooling strategy to reduce the blade temperature. In this study, a united blade cooling strategy was developed by adopting a two-pass ribbed cooling channel with wavy tape for the reason that ribs are near-wall turbulence promoters while the wavy tape is core-region promoter with relatively lower pressure-drop penalty. Ribs and wavy tape may complement each other in the cooling channel. The synergistic effect of the combined near-wall and core-region heat transfer promoter was numerically studied for Reynolds numbers from 6000 to 30000. Two key geometrical factors, namely rib to wave crest phase shift and relative wave amplitude, have significant effect on the thermal performance. The results demonstrate that wavy tape with different phase shift configurations can eliminate the lower heat transfer areas and produce more uniform heat transfer. The 0° phase shift achieved best overall thermal performance, which provided 1.07-1.08 times the flat tape heat transfer enhancement with 1.09-1.11 times the pressure drop penalty. The better heat performance is due to the secondary flow induced by wavy tape, which enhances the fluid mixing between near-wall and core-region.
KEYWORDS
PAPER SUBMITTED: 2021-12-26
PAPER REVISED: 2022-03-12
PAPER ACCEPTED: 2022-03-17
PUBLISHED ONLINE: 2022-05-22
DOI REFERENCE: https://doi.org/10.2298/TSCI211226064J
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2022, VOLUME 26, ISSUE Issue 6, PAGES [4657 - 4668]
REFERENCES
  1. Han, J., Heat transfer and friction in channels with two opposite rib - roughened walls , Journal of heat transfer , 106 (1984), 4, pp. 774 - 781
  2. Han, J. , et al. , Heat transfer enhancement in channels with turbulence promoters , Journal of Engineering for Gas Turbines and Power , 107 (1985), 3, pp. 628 - 635
  3. Han, J., Park, J.S., Developing heat transfer in rectangular channels with rib turbulators , International journal of heat and mass transfer , 31 (1988), 1, pp. 183 - 195
  4. Han, J. , et al. , Augmented heat transfer in rectangular channels of narrow aspect ratios with rib turbulators , International Journal of Heat and Mass Transfer , 32 (1989), 9, pp. 1619 - 1630
  5. Chandra, P.R. , et al. , Effect of Rib Angle on Local Heat/Mass Transfer Distribution in a Two - Pass Rib - Roughened Channel , Journal of Turbomachinery , 110 (1988), 2, pp. 23 3 - 241
  6. Han, J. , et al. , Local heat/mass transfer distributions around sharp 180 deg turns in two - pass smooth and rib - roughened channels , Journal of Heat Transfer , 110 (1988), 1, pp. 91 - 98
  7. Chyu, M.K., Regional Heat Transfer in Two - Pass and Three - Pass Passages With 180 - deg Sharp Turns , Journal of Heat Transfer , 113 (1991), 1, pp. 63 - 70, DOI No. 10.1115/1.2910553
  8. Huh, M. , et al. , Effect of rib height on heat transfer in a two pass rectangular channel (AR= 1: 4) with a sharp entrance at high rotation numbers , International Journal of Heat and Mass Transfer , 52 (2009), 19 - 20, pp. 4635 - 4649
  9. Huh, M. , et al. , Influence of channel orientation on heat transfer in a two - pass smooth and ribbed rectangular channel (AR= 2: 1) under large rotation numbers , Journal of turbomachinery , 134 (2012), 1, p. 011022
  10. Liu, H., Wang, J., Numerical investigation on synthetical performances of fluid flow and heat transfer of semiattached rib - channels , International Journal of Heat and Mass Transfer , 54 (2011), 1 - 3, pp . 575 - 583
  11. Xie, G. , et al. , Turbulent flow characteristics and heat transfer enhancement in a square channel with various crescent ribs on one wall , International Journal of Heat and Mass Transfer , 115 (2017), pp. 283 - 295
  12. Rana, J., et al ., Computational fluid dynamics analysis of a V - rib with gap roughened solar air heater, Thermal Science, 22 (2018), 2, pp. 963 - 972
  13. Nine, M.J., et al ., Turbulence and pressure drop behaviors around semicircular ribs in a rectangular channel, Thermal Science, 18 (2014), 2, pp. 419 - 430
  14. Sahel, D., et al., Effect of the size of graded baffles on the performance of channel heat exchangers, Thermal Science , 24 (2020), 2 Part A, pp. 767 - 775

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence