Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Impingement heat transfer within 1 row of circular water jets : Part 1-Effects of nozzle configuration

1열 원형 충돌수분류군에 의한 열전달의 실험적 연구 (제1보, 노즐형상의 영향)

  • 엄기찬 (인하공업전문대학 기계설계과) ;
  • 김상필 (동양공업전문대학 공장자동화과)
  • Published : 2000.01.01
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Abstract

Experiments were carried out to obtain the effects of nozzle configuration and jet to jet spacing on the heat transfer characteristics of single line of circular water jets impinging on a constant heat flux plane surface. The nozzle configurations are Cone type, Reverse cone type and Vertical circular type, and the nozzle arrays are single jet(nozzle dia. 8 mm), 1 row of 3 jets and 1 row of 5 jets. Jet velocities ranging from 3m/s to 8m/s were investigated for the nozzle to target plate spacing of 80 mm. For the Cone and Reverse cone type nozzle arrays, the average Nusselt number of 1 row of 5 jets was larger than that of 1 row of 3 jets at Re$_{D}$<45000, but that of 1 row of 3 jets was larger than that of 1 row of 5 jets at $Reo\le45000$. For the Vertical circular type nozzle, however, the average Nusselt number of 1 row of 3 jets was larger than that of 1 row of 5 jets at all jet velocities. In the condition of fixed mass flow rates, the maximum heat transfer augmentation was obtained for 1 row of 5 jets and was over 2 times larger than that of the single jet for all nozzle configurations. The nozzle configurations that produce the maximum average Nusselt number are as follows: For 1 row of 3 jets, the Vertical circular type at $Reo\le45000$ and the Reverse cone type at $Reo\le45000$. But, they are the Reverse cone type at Re$_{D}$<55000 and the Vertical circular type at$Reo\le55000$ for 1 row of 5 jets.

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References

  1. 대한기계학회 논문집(B) v.21 no.9 단일수분류 및 수분류군에 의한 열전달(2)-1열 수분류군- 엄기찬;이종수;금성민
  2. ASME J. Heat Transfer v.116 Correlating equations for impingement cooling of small heat sources with multiple circular liquid jets Womac, D. J.;Incropera, F. P;Ramadhyani, S.
  3. ASME J. Heat Transfer v.117 Heat transfer characteristics of arrays of free-surface liquid jets Pan, Y.;Webb, B. W.
  4. ASME J. Heat Transfer v.109 Impingement heat transfer within arrays of circular jets: Part. 1-Effects of minimum, intermediate, and complete crossflow for small and large spacings Obot, N. T.;Trabold, T. A.
  5. ASME J. Heat Transfer v.105 Local heat transfer to staggered arrays of impinging circular air jets Behbahani, A. I.;Goldstein, R. J.
  6. J. Electrochem. Soc. v.137 no.6 Overall mass transfer between a solid surface and submerged or unsubmerged liquid multijets Bensmaili, A.;Coueret, F.
  7. Int. J. Heat Mass Transfer v.19 Local and average transfer coefficients due to an average transfer coefficients due to an impinging row of jets Koopman, R. N.;Sparrow, E. M.
  8. ASME J. Heat Transfer v.116 Effects of interactions between adjoining rows of circular, free surface jets on local heat transfer from the impingement surface Slayzak, S. J.;Viskanta, R.;Incropera, F. P.
  9. ASME J. Engng. for Power Effects of crossflow on impingement heat transfer Metzger, D. E.;Korstad, R. J.
  10. AIAA Journal v.15 no.2 Mixing of a row of jets with a confined cross flow Holdman, J. D.;Walker, R. E.
  11. 대한기계학회논문집(B) v.21 no.9 단일수분류 및 수분류군에 의한 열전달(1)-단일수분류- 엄기찬;이종수;유지오