TY - JOUR
T1 - Void fraction development in gas-liquid flow after a U-bend in a vertically upwards serpentine-configuration large-diameter pipe
AU - Almabrok, Almabrok A.
AU - Aliyu, Aliyu M.
AU - Baba, Yahaya D.
AU - Lao, Liyun
AU - Yeung, Hoi
PY - 2018/1/1
Y1 - 2018/1/1
N2 - We investigate the effect of a return U-bend on flow behaviour in the vertical upward section of a large-diameter pipe. A wire mesh sensor was employed to study the void fraction distributions at axial distances of 5, 28 and 47 pipe diameters after the upstream bottom bend. The study found that, the bottom bend has considerable impacts on up-flow behaviour. In all conditions, centrifugal action causes appreciable misdistribution in the adjacent straight section. Plots from WMS measurements show that flow asymmetry significantly reduces along the axis at L/D = 47. Regime maps generated from three axial locations showed that, in addition to bubbly, intermittent and annular flows, oscillatory flow occurred particularly when gas and liquid flow rates were relatively low. At this position, mean void fractions were in agreement with those from other large-pipe studies, and comparisons were made with existing void fraction correlations. Among the correlations surveyed, drift flux-type correlations were found to give the best predictive results.
AB - We investigate the effect of a return U-bend on flow behaviour in the vertical upward section of a large-diameter pipe. A wire mesh sensor was employed to study the void fraction distributions at axial distances of 5, 28 and 47 pipe diameters after the upstream bottom bend. The study found that, the bottom bend has considerable impacts on up-flow behaviour. In all conditions, centrifugal action causes appreciable misdistribution in the adjacent straight section. Plots from WMS measurements show that flow asymmetry significantly reduces along the axis at L/D = 47. Regime maps generated from three axial locations showed that, in addition to bubbly, intermittent and annular flows, oscillatory flow occurred particularly when gas and liquid flow rates were relatively low. At this position, mean void fractions were in agreement with those from other large-pipe studies, and comparisons were made with existing void fraction correlations. Among the correlations surveyed, drift flux-type correlations were found to give the best predictive results.
KW - Two phase flow
KW - pressure drop
KW - pressure loss
UR - http://www.scopus.com/inward/record.url?scp=85026498979&partnerID=8YFLogxK
U2 - 10.1007/s00231-017-2118-0
DO - 10.1007/s00231-017-2118-0
M3 - Article
AN - SCOPUS:85026498979
VL - 54
SP - 209
EP - 226
JO - Heat and Mass Transfer
JF - Heat and Mass Transfer
SN - 0947-7411
IS - 1
ER -
