TY - JOUR
T1 - Conjugate heat transfer on full-coverage film cooling with array jet impingements with various Biot numbers
AU - Jung, Eui Yeop
AU - Chung, Heeyoon
AU - Choi, Seok Min
AU - Cho, Hyung Hee
N1 - Publisher Copyright:
© 2016 Elsevier Inc.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2017
Y1 - 2017
N2 - Total cooling effectiveness was determined on a film cooled surface with staggered array jet impingement cooling at various Biot numbers. Heat transfer experiments were conducted using infra-red thermography for materials of three thermal conductivities: stainless steel (k = 13.4 W/m K), Corian (k = 1 W/m K), and polycarbonate (k = 0.2 W/m K). Conjugated heat transfer was analyzed with the combined effects of conduction through the test plates and convective heat transfer due to the arrayed jet impingement. The inclination angle of the film cooling holes was 35° and that of the jet impingement holes was 90°. The film and jet impingement holes on each plate were arranged in staggered patterns, and the film cooling holes and jet impingement holes were also positioned in a staggered pattern. The jet Reynolds number, based on hole diameter, was 3000 and the equivalent blowing ratio was 0.3. The diameter of the film cooling holes and the jet impingement holes was 5 mm. The distance between jet and film hole plates was varied in the range 1 ⩽ H/d ⩽ 5. Total cooling effectiveness was measured with and without jet impingement. When jet impingement was added to the internal cooling, the averaged total cooling effectiveness was enhanced about 8.4%. At low Biot numbers, meaning that cooling performance dominated over the conduction effect, the temperature distribution became more uniform due to higher conductive heat transfer. The total cooling effectiveness was strongly related to the Biot number of the plate, and the correlation between total cooling effectiveness at various Biot numbers was determined to predict the total cooling effectiveness in an actual gas turbine engine. The effect of H/d ratio was limited, to within 2.7%.
AB - Total cooling effectiveness was determined on a film cooled surface with staggered array jet impingement cooling at various Biot numbers. Heat transfer experiments were conducted using infra-red thermography for materials of three thermal conductivities: stainless steel (k = 13.4 W/m K), Corian (k = 1 W/m K), and polycarbonate (k = 0.2 W/m K). Conjugated heat transfer was analyzed with the combined effects of conduction through the test plates and convective heat transfer due to the arrayed jet impingement. The inclination angle of the film cooling holes was 35° and that of the jet impingement holes was 90°. The film and jet impingement holes on each plate were arranged in staggered patterns, and the film cooling holes and jet impingement holes were also positioned in a staggered pattern. The jet Reynolds number, based on hole diameter, was 3000 and the equivalent blowing ratio was 0.3. The diameter of the film cooling holes and the jet impingement holes was 5 mm. The distance between jet and film hole plates was varied in the range 1 ⩽ H/d ⩽ 5. Total cooling effectiveness was measured with and without jet impingement. When jet impingement was added to the internal cooling, the averaged total cooling effectiveness was enhanced about 8.4%. At low Biot numbers, meaning that cooling performance dominated over the conduction effect, the temperature distribution became more uniform due to higher conductive heat transfer. The total cooling effectiveness was strongly related to the Biot number of the plate, and the correlation between total cooling effectiveness at various Biot numbers was determined to predict the total cooling effectiveness in an actual gas turbine engine. The effect of H/d ratio was limited, to within 2.7%.
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U2 - 10.1016/j.expthermflusci.2016.12.008
DO - 10.1016/j.expthermflusci.2016.12.008
M3 - Article
AN - SCOPUS:85007478263
VL - 83
SP - 1
EP - 8
JO - Experimental Thermal and Fluid Science
JF - Experimental Thermal and Fluid Science
SN - 0894-1777
ER -