A comparative study of flow boiling heat transfer and pressure drop characteristics in a pin-finned heat sink at horizontal/ vertical upward flow orientations
发布时间：2025-04-30
点击次数：
- 发布时间：
- 2025-04-30
- 论文名称：
- A comparative study of flow boiling heat transfer and pressure drop characteristics in a pin-finned heat sink at horizontal/ vertical upward flow orientations
- 发表刊物：
- ASME J Heat Mass Transfer
- 摘要：
- With the continuous development of power electronic devices toward miniaturization and compactness, it is necessary to develop more efficient flow boiling heat transfer technologies. In this work, the flow boiling heat transfer and pressure drop characteristics of Novec649 in a pin finned channel under two kinds of flow orientations (horizontal and vertical upward) are experimentally investigated. Heat flux, inlet flow velocity, and inlet subcooling are considered as the variable parameters. The results show that among all boiling operating conditions, the heat transfer performances between two orientations are basically consistent, while the pressure drop of vertical upward pin finned channel is relativelylower,indicatingthatthecomprehensiveflowboilingheattransferperformanceof vertical oriented channel is better. Subsequently, a series of flow visualization experiments are performed in vertical upward pin finned channel. With the increase of heat flux, four kinds of flow pattern are discovered in the order of dispersed bubble flow, bubble flow, homogeneous flow, and annular flow. In the region of annular flow, although a vapor flow has already formed in the channel, there is still a large amount of liquid phase surrounding the wall and pin fins. Therefore, no obvious heat transfer deterioration was observed in the pin finned channel. Along the flow direction, the diameter of bubbles will increase first, and then present obvious oscillation. As the heat flux increases, both the average bubble detachment diameter and the frequency increase correspondingly. As the fluid velocity increases, the average bubble detachment diameter presents a downward trend, while the average bubble detachment frequency presents an upward trend.
- 合写作者：
- Bin Hu, Di Qi, Yongsheng Xu, Mei Lin, Qiuwang Wang
- 卷号：
- 146(1)
- 页面范围：
- 011006
- 是否译文：
- 否
- 发表时间：
- 2024-01-05