TY - GEN
T1 - Two-phase pressure drop of CO2 in mini tubes and microchannels
AU - Yun, R.
AU - Kim, Y.
PY - 2003
Y1 - 2003
N2 - Two-phase pressure drops of CO2 are investigated in mini tubes with inner diameters of 2.0 and 0.98 mm and in microchannels with hydraulic diameters from 1.08 to 1.54 mm. For the mini tubes, the tests were conducted with a variation of mass flux from 500 to 3570 kg/m2s, heat flux from 7 to 48 kW/m2, while maintaining saturation temperatures at 0°C, 5°C and 10°C. For the microchannels, mass flux was varied from 100 to 400 kg/m2s, and heat flux was altered from 5 to 20 kW/m 2. A direct heating method was used to provide heat into the refrigerants. The pressure drop of CO2 in mini tubes shows very similar trends with that in large diameter tubes. Although the microchannel has a small hydraulic diameter, two-phase effects on frictional pressure drop are significant. The Chisholm parameter of the Lockhart and Martinelli correlation is modified by considering diameter effects on the two-phase frictional multiplier.
AB - Two-phase pressure drops of CO2 are investigated in mini tubes with inner diameters of 2.0 and 0.98 mm and in microchannels with hydraulic diameters from 1.08 to 1.54 mm. For the mini tubes, the tests were conducted with a variation of mass flux from 500 to 3570 kg/m2s, heat flux from 7 to 48 kW/m2, while maintaining saturation temperatures at 0°C, 5°C and 10°C. For the microchannels, mass flux was varied from 100 to 400 kg/m2s, and heat flux was altered from 5 to 20 kW/m 2. A direct heating method was used to provide heat into the refrigerants. The pressure drop of CO2 in mini tubes shows very similar trends with that in large diameter tubes. Although the microchannel has a small hydraulic diameter, two-phase effects on frictional pressure drop are significant. The Chisholm parameter of the Lockhart and Martinelli correlation is modified by considering diameter effects on the two-phase frictional multiplier.
UR - http://www.scopus.com/inward/record.url?scp=1242331523&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=1242331523&partnerID=8YFLogxK
U2 - 10.1115/icmm2003-1062
DO - 10.1115/icmm2003-1062
M3 - Conference contribution
AN - SCOPUS:1242331523
SN - 0791836673
SN - 9780791836675
T3 - International Conference on Microchannels and Minichannels
SP - 507
EP - 511
BT - International Conference on Microchannels and Minichannels
PB - American Society of Mechanical Engineers
T2 - First International Conference on Microchannels and Minichannels
Y2 - 24 April 2003 through 25 April 2003
ER -