TY - JOUR
T1 - A parametric study of nucleate boiling on structured surfaces part II
T2 - Effect of pore diameter and pore pitch
AU - Chien, Liang Han
AU - Webb, Ralph L.
PY - 1996
Y1 - 1996
N2 - This two-part experimental work identifies the effect of geometric dimensions on the boiling performance of "tunneled" enhanced boiling surfaces. The surface is formed on an integral-fin tube having a copper foil wrapped over the fin tips. Pores of known diameter and pitch are pierced in the foil cover. The resulting surface is similar to the Hitachi Thermoexcel-E tube. Tests were performed on a 19.1 mm diameter, horizontal tube using R-11 and R-123 at 26.7°C for heat fluxes between 2-to-70 kW/m2. The cylindrical glass test cell permitted viewing of the boiling process. This second part of the study defines the effect of the pore dimensions (pore diameter and pore pitch) using 35 and 50 fins/in tubes having 0.9 mm or 0.5 mm fin height. The pore diameters are 0.12, 0.18, 0.23, and 0.28 mm and the pore pitches are 0.75, 1.5, and 3.0 mm. The results are interpreted to explain the relationship between pore diameter and pore pitch on the boiling performance. For a given pore pitch, a higher dry out heat flux is obtained using larger pore size. At a certain heat flux, part of the tunnel becomes flooded and the performance will be reduced. Smaller pore size will inhibit flooding at reduced heat flux.
AB - This two-part experimental work identifies the effect of geometric dimensions on the boiling performance of "tunneled" enhanced boiling surfaces. The surface is formed on an integral-fin tube having a copper foil wrapped over the fin tips. Pores of known diameter and pitch are pierced in the foil cover. The resulting surface is similar to the Hitachi Thermoexcel-E tube. Tests were performed on a 19.1 mm diameter, horizontal tube using R-11 and R-123 at 26.7°C for heat fluxes between 2-to-70 kW/m2. The cylindrical glass test cell permitted viewing of the boiling process. This second part of the study defines the effect of the pore dimensions (pore diameter and pore pitch) using 35 and 50 fins/in tubes having 0.9 mm or 0.5 mm fin height. The pore diameters are 0.12, 0.18, 0.23, and 0.28 mm and the pore pitches are 0.75, 1.5, and 3.0 mm. The results are interpreted to explain the relationship between pore diameter and pore pitch on the boiling performance. For a given pore pitch, a higher dry out heat flux is obtained using larger pore size. At a certain heat flux, part of the tunnel becomes flooded and the performance will be reduced. Smaller pore size will inhibit flooding at reduced heat flux.
UR - http://www.scopus.com/inward/record.url?scp=4243131751&partnerID=8YFLogxK
M3 - 文章
AN - SCOPUS:4243131751
SN - 0272-5673
VL - 326
SP - 137
EP - 143
JO - American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD
JF - American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD
ER -