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Articles you may be interested inSimulation of gas-liquid two-phase flow based on the Riemann problem AIP Conf. Proc. 1482, 91 (2012); 10.1063/1.4757444 RANS simulation of the planar motion mechanism tests for a VLCC hull AIP Conf.Abstract. In order to get more local interfacial information as well as to further comprehend the intrinsic mechanism of two-phase flow under rolling condition to improve and extend the two-fluid model in rolling condition, an experimental investigation of two-phase flow under rolling as well as vertical steady condition was conducted by using double-sensor optical probe fabricated by the authors. The experimental loop is fixed on a rolling platform, which can simulate the rolling movement of a ship with the rolling period and rolling angle in the ranges of 0-20s and 0-45°, respectively. An optical probe driven by a mechanical traverser is installed on the test section, wherein making it move diametrically. Experimental investigations were conducted on this experimental loop for air-water two-phase flow under rolling and steady conditions. Local void fraction, interfacial area concentration (IAC) and bubble velocity were obtained for further improving the interface transportation equation. Both the measured void fraction and IAC demonstrated wall peak or core peak distributions under vertical condition. The typical distribution of IAC under vertical conditions showed that IAC changes from wall peak to core peak with the gas flow rate increasing; while as the liquid flow rate increases, the distribution changes inversely. In the case of rolling conditions, despite similar to the distribution under vertical condition, the local time-averaged void fraction and IAC have lower value in centerline and high value near wall region. The results also indicated that the rolling amplitude has an influence on the local bubble frequency, void fraction and IAC, except interface velocity, while rolling period almost has no effect on the local characteristics.Since the two-fluid model [1] was proposed, it has achieved increasing importance in nuclear reactor accident and safety analysis. Due to dealing with the phases separately in terms of the conservation equations in mass, momentum, and energy, and characterizing the interactions between the two phases in the interfacial transfer terms, this model requires a detailed knowledge of the interfacial structure, such as interfacial area concentration (IAC) and so on. As the complicated transfer mechanisms at the interface coupled with the motion and distortion of the interface, the constitutive equations for interfacial transfer terms are the weakest link in two-fluid model. So Kocamustafaogullari and Ishii [2] established the foundations of the interfacial transport equation to solve the closure problem for IAC in two-fluid model. Then Wu et al [3] formulated a one-group interfacial transport equation (IATE) for bubbly flow. Faced with the limited application of spherical and distorted bubble shapes, Fu et al [4] and Sun et al [5] developed theoretical m...

Gas-liquid slug flow is widely encountered in many practical industrial applications. A detailed understanding of the hydrodynamics of the liquid slug is of great importance in modeling the slug flow. A visualized study using a high speed video camera system was conducted to study liquid slug characteristics of slug flow in a vertical narrow rectangular channel (3.25×40mm2). It is found that three regions could be distinguished in the stable liquid slug tagging along the leading gas slug in most cases. The characteristics of a gas slug are greatly influenced by its position in the liquid slug, and the leading slug has a significant effect on the trailing slug in laminar or transition flow. The wake region of leading slug is also actually a sudden enlargement region where the water jet out of the liquid flim. The minimum stable liquid slug length Lmin is obtained in the experiments ranging from 9 to 17Dh in fully developed turbulence flow.

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