水平円柱下流の気液界面積濃度分布の遷移

Abstract

Measurements of the interfacial area concentration and the void fraction in a vertical upward air-water two-phase flow downward of single horizontal tube and horizontal tube bundle were carried out by a double sensor electrical conductivity probe. The test section comprised a 50mm × 50mm square channel partially obstructed by the single horizontal tube and the horizontal tube bundle inside. Five types of the test sections which the horizontal tube arrangement is different were used to provide various distributions of air-water two-phase flow downstream of the test section. The superficial gas velocity and superficial liquid velocity ranged from 0.02 to 0.20 m/s and from 0.13 to 0.53 m/s, respectively. Local flow measurements were performed at the three axial locations of z (z') = 110 (70), 340 (300), and 640 (600) mm and the transverse locations from r = 3 to 25 mm. The single horizontal tube and the horizontal tube bundle effect the distributions of the interfacial area concentration and the void fraction at z (z') = 110 (70). This effect was decreased along the flow direction due to the diffusion of bubble toward horizontal direction. At high gas flow rate conditions, void fraction increase, while interfacial area concentration decrease with increasing gas flow rate because of the bubble coalescence.