RT Journal Article
ID 421767e6193531de
A1 Jennerjohn, Mary
A1 Lee, Junsik
A1 Ren, Zhong
A1 Ligrani, Phillip
A1 McQuilling, Mark
A1 Fox, Michael D.
A1 Moon, Hee-Koo
T1 JET ARRAY IMPINGEMENT COOLING LOCAL NUSSELT NUMBER VARIATIONS: EFFECTS OF HOLE ARRAY SPACING, JET-TO-TARGET PLATE DISTANCE, AND REYNOLDS NUMBER
JF Heat Transfer Research
JO HTR
YR 2016
FD 2016-02-10
VO 47
IS 2
SP 119
OP 140
K1 impingement jets
K1 impingement cooling
K1 heat transfer augmentation
K1 gas turbine
AB Discussed in the article are the combined and separate effects of hole array spacing, jet-to-target plate distance, and Reynolds number on the local surface heat transfer rate for an impinging jet array. The array of impinging jets is directed to one flat surface of a channel which is bounded on three sides. Considered are the Reynolds numbers ranging from 8000 to 50,000, jet-to-target plate distances of 1.5D, 3.0D, 5.0D, and 8.0D, and the streamwise and spanwise hole spacing of 5D, 8D, and 12D, where D is the impingement hole diameter. Also included is a conduction analysis of the impingement cooling array target surface. In general, the local Nusselt numbers generally increase at each x/D location as either the Reynolds number increases, or as the X/D = Y/D hole spacing decreases. The highest Nusselt numbers are generally present at Z/D = 3.0 for Rej values of 8200, 20,000, and 30,000. When Rej = 52,000, the highest measured Nusselt number values are generally present for Z/D of either 1.5, 3.0, or 5.0, depending on the magnitudes of Rej, X/D, Y/D, and streamwise location x/D. The cumulative accumulations of crossflows, from sequential rows of jets, result in sequentially decreasing periodic Nusselt number variations with streamwise development. When examined at a particular value of Rej, the streamwise locations of the local maximum Nusselt numbers also shift to larger x/D locations as Z/D, the normalized jet-to-target distance, increases. The overall result is a complex dependence of local Nusselt numbers on the hole array spacing, jet-to-target plate distance, and impingement jet Reynolds number.
PB Begell House
LK https://www.dl.begellhouse.com/journals/46784ef93dddff27,49d564d677f1e773,421767e6193531de.html