This paper reports slug bubble dynamics on modified surface with two-dimensional graphene film in downward-facing nucleate boiling. Behaviors of slug bubbles were observed with high speed camera, and post-processing was followed to measure departing speed, frequency, and diameter of slug bubbles, which were important to analyze boiling performance change. The graphene-modified surface showed enhanced boiling heat transfer coefficient (BHTC) and critical heat flux (CHF). The effect of surface modification on slug bubble dynamics was quantitatively analyzed; bigger slugs departed from the modified surface with faster speed but same frequency, compared with the bare. It seems that the BHTC enhancement is caused by increase of bubble diameter, resulting in increase of its departing speed. The higher speed of departing bubble could extend the hydrodynamic limit of vapor removal from downward-facing surface, so that CHF performance could be enhanced.

ABSTRACT
1. 서 론
2. 실 험
    2.1 그래핀 필름을 이용한 표면개질
    2.2 실험징치 및 실험수행방법
    2.3 가시화 및 후처리 방법
3. 실험결과 및 토의
4. 결 론
References

• 김지민(한국교원대학교) | Kim Jimin