Experimental studies of interfacial area in a horizontal slug flow

Book · Tue Dec 31 04:00:00 EST 1996

OSTI ID:442592

Riznic, J R ^[1]; Lewis, S P; Kojasoy, G ^[2]

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1. Atomic Energy Control Board, Ottawa, Ontario (Canada). Safety Evaluation Div.
2. Univ. of Wisconsin, Milwaukee, WI (United States). Mechanical Engineering Dept.

The thermal-hydraulic behavior of simultaneous flow of gas and liquid has been of great interest to practicing engineers, since it is often encountered in industrial applications such as nuclear and fossil fueled power plants, petro-chemical and process apparatus and plants, refrigeration equipment, and various multiphase heat exchangers. The internal flow structure of horizontal slug flow has been experimentally investigated by measuring the local interfacial area concentration, void fraction and interfacial velocity distribution. The four-sensor electroresistivity probe was used to detect the instantaneous interface velocities and interfacial area. Experimental studies were performed on the plug/slug flow regimes with an air-water system. Data were acquired at the axial location of L/D = 253 from the mixing chamber. Four different liquid flow rates in combination with five different gas injection rates were studied. The superficial liquid velocity was varied between 0.55 and 2.20 m/s and gas velocity between 0.27 and 2.20 m/s. With these experimental conditions, the total void fraction, including contributions from small and large slug bubbles, ranged from 10 to 70%. The void fraction measurements were checked against the raw signal data, high speed video recordings, and measurements obtained by the hot film anemometer probe. The agreement between the data was very good, confirming that the four-sensor probe measurements can be performed with a high degree of confidence. In the region of transition between plug and slug flow regime, with an increase in the gas flow rate, the number and contribution of the small follow-up bubbles increased. The increase in the liquid flow rate produced similar effects. The slug bubble frequency also increased with an increase in the gas velocity and also slugs are longer at higher gas flow rates.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• OSTI ID: 442592
• Report Number(s): CONF-961105--; ISBN 0-7918-1521-8
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
BUBBLES
EXPERIMENTAL DATA
FLOW RATE
HYDRODYNAMICS
INTERFACES
TEST FACILITIES
TWO-PHASE FLOW
VOID FRACTION