Mobile QR Code QR CODE : Korean Journal of Air-Conditioning and Refrigeration Engineering
Korean Journal of Air-Conditioning and Refrigeration Engineering

Korean Journal of Air-Conditioning and Refrigeration Engineering

ISO Journal TitleKorean J. Air-Cond. Refrig. Eng.
  • Open Access, Monthly
Open Access Monthly
  • ISSN : 1229-6422 (Print)
  • ISSN : 2465-7611 (Online)
Title Flow Characteristics of a Gas-Liquid Slug Flow in Small Vertical Tubes
Authors 계석현(Seok-Hyun Kye) ; 김동선(Dong-Seon Kim)
DOI http://dx.doi.org/10.6110/KJACR.2013.25.5.246
Page pp.246-254
ISSN 1229-6422
Keywords 슬러그 유동 ; 관경 ; 기포 속도 ; 기포 길이 ; 액막 두께 Slug flow ; Tube diameter ; Bubble velocity ; Bubble length ; Film thickness
Abstract Some characteristics of nitrogen-water slug flow were optically measured, in vertical acrylic tubes of 2, 5 and 8 mm diameter. Bubble velocity, bubble and unit cell lengths were measured, by analyzing the light intensity signals from two sets of dot laser-infrared sensor modules mounted along the transparent tubes. Optical images of the bubbles were also taken and analyzed, to measure bubble shapes and liquid film thickness. It was found that the measured bubble velocities were in good agreement with the empirical models in the literature, except for those measured under high superficial velocity condition in the 2 mm tube. Bubble length was found to be the longest in the 2 mm tube, being 4 to 5 times those of the other tubes. Liquid film was found to have developed early in the 2 mm tube, which made the blunt shape of the bubble head. Liquid film thickness in the 8 mm tube was measured at almost twice those of the other tubes.