단열 원관내 공기-물 기-액 이상류의 유동특성 = Flow Characteristics of Air-Water Gas-liquid Two-Phase Flows in an Adiabatic Tube

다국어 초록 (Multilingual Abstract)

Two-phase loop systems using the latent heat capacity of their working fluids can meet the increasing power requirements and are well suited to thermal management systems of future large applications, due to its abilities to handle large heat loads and to provide them at uniform temperatures regardless of the changes in the heat loads. However, more reliable design of thermal transport, power acquisition and thermal management systems requires a through understanding of the flow hydrodynamic. Therefore some experiments were performed for an water-air two-phase flow through 10㎜ diameter adiabatic test section with 600㎜ length of transparent acrylic resin tube. The obtained experimental data covered a range of liquid and gas flow rates with the liquid superficial velocity ranging from 0.095㎧ to 2.56 Necessities of high power level demands for thermal management systems in future space applications have stimulated research on gas-liquid two-phase flows under microgravity condition. Two-phase flow is an excellent alternative to the conventional single-phase system in transporting large amount of thermal energy at a uniform temperature regardless of variations in the heat loads. In addition, two-phase flows exist in a wide range of applications and enabling technologies in space. These include material processing and ceramics at ultra high temperatures, life-support systems, storage and transport of cryogenics, and in the design of many cold plate assemblies where heating or cooling takes place at the instrument interface. More reliable design of such systems requires a through understanding of the mechanics of the two-phase flow at variable gravity conditions, since two-phase flow characteristics differ when subjected to earth gravity, to hyper-gravity, to Moon or Mars gravity, or to microgravity environment. The essential factors to the designers of such systems are also the flow patterns in a conduit, the void fraction, and the pressure drop at different gas and liquid flow rates. Recent progress in the study of gas-liquid two-phase flows at variable gravity conditions will be reviewed and discussed in this paper., and the gas superficial velocity ranging from 0.032㎧ to 21.08㎧. As results, The flow patterns were depended on the superficial velocity of each phase. It showed that the increasing jL resulted in a significant increase in the frictional pressure loss for all flow patterns, at a constant jc. The experimental results were also evaluated with some of existing flow pattern and frictional pressure drop models and correlations.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 실험장치 및 방법
• 3. 유동양식
• 4. 보이드율과 슬립비
• 5. 마찰압력손실과 보이드율
• 6. 결론
• 참고 문헌