Thekey difference between pool boiling and flow boilingis that pool boiling occurs in the absence of bulk fluid flow, whereas flow boiling occurs in the presence of bulk fluid flow.
Pool boiling is aheat transfer相位从液体到的机制vapor. Flow boiling, on the other hand, is a heat transfer mechanism that occurs when a fluid circulates over a heated surface due to external causes such as a pump or due to the naturalbuoyancy effect.
CONTENTS
1.Overview and Key Difference
2.What is Pool Boiling
3.什么是流沸点
4.Pool Boiling vs Flow Boiling in Tabular Form
5.Summary – Pool Boiling vs Flow Boiling
What is Pool Boiling?
Pool boiling is a heat transfer mechanism in which a phase transition occurs from liquid to vapor. This can happen in the presence of any motion of the fluid occurring due to natural convection currents and the motion of the bubbles under the influence of buoyancy.
The rate of heat transfer in the pool boiling process greatly depends on the number of activenucleation表面上的位置以及每个位点的气泡形成速率。因此,我们可以修改并增强加热表面上的成核,以增强成核沸腾的热传递。此外,诸如粗糙度和污垢之类的不均匀加热表面可以用作沸腾的额外成核位点。
什么是流沸点?
Flow boiling is a heat transfer mechanism that occurs when a fluid circulates over a heated surface due to external causes such as a pump or due to the natural buoyancy effect. In other words, in the process of flow boiling, the fluid is forced to move in a heated pipe or over a surface by external means.
This is also known as external forced convection boiling. Here, the fluid undergoes phase change upon moving through an external source such as a pump. In this case, the boiling tends to exhibit combined effects of convection and pool boiling. We can classify flow boiling as either external or internal flow boiling. In external flow boiling, the higher the velocity, the higher the nucleate boiling heat flux and the critical heat flux. There are different flow regimes related to flow boiling, which include:
- Liquid-single-phase flow
- 气泡流动
- Slug flow
- Annular flow
- Mist flow
- Vapor-single-phase flow
池沸腾和Fl之间的区别是什么ow Boiling?
Pool boiling is a heat transfer mechanism in which a phase transition occurs from liquid to vapor. Flow boiling, on the other hand, is a heat transfer mechanism that occurs when a fluid circulates over a heated surface due to external causes such as a pump or due to the natural buoyancy effect. Pool boiling and flow boiling are important boiling techniques. The key difference between pool boiling and flow boiling is that pool boiling occurs in the absence of bulk fluid flow, whereas flow boiling occurs in the presence of bulk fluid flow.
Below is a summary of the difference between pool boiling and flow boiling in tabular form for side by side comparison.
Summary – Pool Boiling vs Flow Boiling
Pool boiling is a heat transfer mechanism in which a phase transition occurs from liquid to vapor. Flow boiling, on the other hand, is a heat transfer mechanism that occurs when a fluid circulates over a heated surface due to external causes such as a pump or due to the natural buoyancy effect. The key difference between pool boiling and flow boiling is that pool boiling occurs in the absence of bulk fluid flow, whereas flow boiling occurs in the presence of bulk fluid flow.
Reference:
1. Roh, Heui-Seol. “Heat Transfer Mechanisms in Pool Boiling.”国际热与传播杂志, Pergamon, 12 Oct. 2013.
Image Courtesy:
1. “沸腾,水,热,游泳池,春天,水” (CC0) via Pixabay
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