An experimental and numerical investicration on a confined impinging air jet at high Reynolds numbers


Baydar E., OZMEN Y.

APPLIED THERMAL ENGINEERING, vol.25, pp.409-421, 2005 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 25
  • Publication Date: 2005
  • Doi Number: 10.1016/j.applthermaleng.2004.05.016
  • Journal Name: APPLIED THERMAL ENGINEERING
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.409-421
  • Keywords: jet impingement, subatmospheric region, pressure coefficient, turbulence, k-epsilon model, TURBULENCE MODEL ASSESSMENT, HEAT-TRANSFER, FLOW-FIELD, CIRCULAR JET, CROSS-FLOW, FLAT-PLATE, SLOT JETS, IMPINGEMENT, PLANE, PREDICTIONS

Abstract

An experimental and numerical study is carried out to investigate flow field of a confined jet issuing from the lower surface and impinging normally on the upper surface. The mean velocity, turbulence intensity and pressure distributions in the impingement re-ion were obtained for Reynolds numbers ranging from 30,000 to 50,000 and a nozzle-to-plate spacing range of 0.2-6. The effects of Reynolds number and nozzle-to-plate spacing on the flow structure are examined. A subatmospheric region occurs on the Impingement plate at nozzle-to-plate spacings up to 2 for Reynolds numbers studied and it moves radially outward from the stagnation point with increasing nozzle-to-plate spacing. It is concluded that there exists a linkage among the subatmospheric region, turbulence intensity and heat transfer coefficients. The numerical results obtained using the standard k-epsilon turbulence model are in agreement with the experimental results except for the nozzle-to-plate spacings less than one. (C) 2004 Elsevier Ltd. All rights reserved.