Interfacial area and two-phase flow structure development measured by a double-sensor probe

Technical Report · Mon Jun 01 04:00:00 EDT 1992

DOI:https://doi.org/10.2172/10169682· OSTI ID:10169682

Leung, Waihung; Revankar, S T; Ishii, Yoshihiko; Ishii, Mamoru

In this report, we studied the local phasic characters of dispersed flow regime both at the entrance and at the fully developed regions. Since the dispersed phase is distributed randomly in the medium and enclosed in relatively small interfaces, the phasic measurement becomes difficult to obtain. Local probe must be made with a miniaturized sensor in order to reduce the interface distortion. The double-sensor resistivity probe has been widely used in local void fraction and interface velocity measurements because the are small in comparison with the interfaces. It has been tested and proved to be an accurate local phasic measurement tool. In these experiments, a double-sensor probe was employed to measure the local void fraction and interface velocity in an air-water system. The test section was flow regime can be determined by visualization. Furthermore, local phasic measurements can be verified by photographic studies. We concentrated our study on the bubbly flow regime only. The local measurements were conducted at two axial locations, L/D = 8 and 60, in which the first measurement represents the entrance region where the flow develops, and the second measurement represents the fully developed flow region where the radial profile does not change as the flow moves along the axial direction. Four liquid flow rates were chosen in combination with four different gas injection rates. The superficial liquid velocities were j{sub t} = 1.0, 0.6,0.4, and 0.1 m/s and superficial gas velocities were j{sub g} = 0.0965, 0.0696, 0.0384, and 0.0192 m/s. These combinations put the two-phase flow well in the bubbly flow regime. In this sequence of phenomenological studies, the local void fraction, interface area concentration, sauter mean diameter, bubble velocity and bubble frequency were measured.

• Research Organization: Purdue Univ., Lafayette, IN (United States). School of Nuclear Engineering
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-90ER14147
• OSTI ID: 10169682
• Report Number(s): DOE/ER/14147--2; PU-NE--92/1; ON: DE92019459
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400
AIR
BUBBLES
CONTINUITY EQUATIONS
EXPERIMENTAL DATA
FLOW RATE
HEAT TRANSFER AND FLUID FLOW
HYDRAULICS
HYDRODYNAMICS
INTERFACES
PHOTOGRAPHY
PIPES
PROBES
SURFACE AREA
TURBULENT FLOW
TWO-PHASE FLOW
VELOCITY
VOID FRACTION
WATER