Pressure drop and holdup studies of air—liquid flow in helical coils

Flow pattern transition, frictional pressure drop, and holdup of gas non‐Newtonian fluid flow in helical tube

“…In order to predict the two‐phase pressure drop and holdup in a coiled tube, the most widely used correlations are based on L‐M parameter. Most of the researchers used the L‐M method to correlate their experimental data for two‐phase frictional pressure drop and holdup while others developed a modified expression for L‐M parameters to fit their experimental data . The L‐M correlation is a recognized tool to describe the two‐phase pressure drop in different flow process system.…”

Flow pattern transition, frictional pressure drop, and holdup of gas non‐Newtonian fluid flow in helical tube

“…In order to predict the two‐phase pressure drop and holdup in a coiled tube, the most widely used correlations are based on L‐M parameter. Most of the researchers used the L‐M method to correlate their experimental data for two‐phase frictional pressure drop and holdup while others developed a modified expression for L‐M parameters to fit their experimental data . The L‐M correlation is a recognized tool to describe the two‐phase pressure drop in different flow process system.…”

Two-phase pressure drop prediction in helically coiled steam generators for nuclear power applications

“…It is evident that the available pressure drop data in usable form on water-steam flows through helically coiled tubes are rather limited, so that more experimental studies are clearly welcome. Since the present study is specifically targeting water-steam two-phase flows, available data generated with fluids other than water-steam [7,9,10,[14][15][16][17][18]21] are not taken into account.…”

“…Available void fraction measurements in helical coils [7,9,10,14,16,18] suggest that curvature effects on the void fraction are small and negligible, so that straight tube void fraction prediction methods can be extrapolated to helically coiled tubes, at least in first approximation. Therefore, the void fraction prediction method of Woldesemayat and Ghajar [51] was used here, as this is one of the most accurate general purpose void fraction correlations currently available for straight tubes [50].…”

Helically Coiled Heat Exchangers

“…Flow of air-water mixture through a helically coiled tube was studied by Whalley (1980) and the flow pattern transition between stratified and annular flow was examined. Rangacharyulu and Davies (1984) experimentally studied pressure drop and hold-up for counter-current upward flow of air-liquid system through copper coils. They proposed a new correlation for two-phase frictional pressure drop based on the modified Lockhart-Martinelli parameter.…”

Flow pattern transition, frictional pressure drop, and holdup of gas non‐Newtonian fluid flow in helical tube

“…In order to predict the two‐phase pressure drop and holdup in a coiled tube, the most widely used correlations are based on L‐M parameter. Most of the researchers used the L‐M method to correlate their experimental data for two‐phase frictional pressure drop and holdup while others developed a modified expression for L‐M parameters to fit their experimental data . The L‐M correlation is a recognized tool to describe the two‐phase pressure drop in different flow process system.…”

Two-phase pressure drop prediction in helically coiled steam generators for nuclear power applications

“…It is evident that the available pressure drop data in usable form on water-steam flows through helically coiled tubes are rather limited, so that more experimental studies are clearly welcome. Since the present study is specifically targeting water-steam two-phase flows, available data generated with fluids other than water-steam [7,9,10,[14][15][16][17][18]21] are not taken into account.…”

“…Available void fraction measurements in helical coils [7,9,10,14,16,18] suggest that curvature effects on the void fraction are small and negligible, so that straight tube void fraction prediction methods can be extrapolated to helically coiled tubes, at least in first approximation. Therefore, the void fraction prediction method of Woldesemayat and Ghajar [51] was used here, as this is one of the most accurate general purpose void fraction correlations currently available for straight tubes [50].…”

Helically Coiled Heat Exchangers

“…Flow of air-water mixture through a helically coiled tube was studied by Whalley (1980) and the flow pattern transition between stratified and annular flow was examined. Rangacharyulu and Davies (1984) experimentally studied pressure drop and hold-up for counter-current upward flow of air-liquid system through copper coils. They proposed a new correlation for two-phase frictional pressure drop based on the modified Lockhart-Martinelli parameter.…”

Flow pattern transition, frictional pressure drop, and holdup of gas non‐Newtonian fluid flow in helical tube

“…In order to predict the two‐phase pressure drop and holdup in a coiled tube, the most widely used correlations are based on L‐M parameter. Most of the researchers used the L‐M method to correlate their experimental data for two‐phase frictional pressure drop and holdup while others developed a modified expression for L‐M parameters to fit their experimental data . The L‐M correlation is a recognized tool to describe the two‐phase pressure drop in different flow process system.…”

Two-phase pressure drop prediction in helically coiled steam generators for nuclear power applications

“…It is evident that the available pressure drop data in usable form on water-steam flows through helically coiled tubes are rather limited, so that more experimental studies are clearly welcome. Since the present study is specifically targeting water-steam two-phase flows, available data generated with fluids other than water-steam [7,9,10,[14][15][16][17][18]21] are not taken into account.…”

“…Available void fraction measurements in helical coils [7,9,10,14,16,18] suggest that curvature effects on the void fraction are small and negligible, so that straight tube void fraction prediction methods can be extrapolated to helically coiled tubes, at least in first approximation. Therefore, the void fraction prediction method of Woldesemayat and Ghajar [51] was used here, as this is one of the most accurate general purpose void fraction correlations currently available for straight tubes [50].…”

Helically Coiled Heat Exchangers

“…Flow of air-water mixture through a helically coiled tube was studied by Whalley (1980) and the flow pattern transition between stratified and annular flow was examined. Rangacharyulu and Davies (1984) experimentally studied pressure drop and hold-up for counter-current upward flow of air-liquid system through copper coils. They proposed a new correlation for two-phase frictional pressure drop based on the modified Lockhart-Martinelli parameter.…”