원형 실린더 주위를 흐르는 기포류 유동의 기포 크기 영향에 대한 실험 연구

다국어 초록 (Multilingual Abstract)

Two-phase cross flow over a bluff body occurs in many thermal and power systems such as steam generators, heat exchangers and nuclear reactors. However, only a few studies have been studied on the fundamental effects of the bubbles around the bluff body. Since the rising bubbles generate intensive liquid agitation, the resultant flow structures and bubble accumulation around the solid body are important to understand the pure bubble effect on flow field. In the present study, the two-phase flow phenomena around a smooth circular cylinder induced by the bubble column in a static water is experimentally investigated while varying the mean bubble sizes from 2 to 4 ㎜ and the void fraction by controlling the spargers separately. For the measurements, we basically use the shadowgraph technique and several image processing algorithms. In the wake behind a circular cylinder, the void distribution shows a specific trend similar to the formation of recirculation region for the single-phase flow, which changes with the mean void fraction and the bubble size. We will analyze this in terms of bubble dynamics and bubble-induced flows on a solid body.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 실험장치 및 방법
• 3. 결과 및 토의
• 4. 결론
• 참고문헌