摘要
一般在沸腾传热实验中壁面的加热方式有电加热和流体加热两种,流体加热方式下的沸腾传热研究进行得很少。在水加热条件下,对水在竖直环形流道内欠热流动沸腾时的气泡行为进行了可视化研究。环隙宽度为5mm和3mm两种,质量流速分别为16.8～55.3kg/(m2.s)和15.3～62.1kg/(m2.s)。可视化实验结果表明:在贴近壁面的区域存在气泡运动层,大部分气泡在气泡运动层内运动。在宽度为3mm的流道中,气泡在脱离壁面前一般会滑动;滑动距离不超过2～3倍气泡直径,并且存在反复胀缩的现象。5mm流道内的气泡则较少发生滑动,往往在脱离壁面后会被弹回壁面。气泡的滑动和离开壁面后又返回壁面的运动方式是沸腾具有高强度传热能力的原因之一。
In the boiling heat transfer setup,the two commonly methods to heat the test section wall are electric heating and fluid heating,and the boiling heat transfer for the latter is seldom studied.The boiling heat transfer characteristics under the two heat methods are different.Visualization research has been con-ducted on the bubble behavior of sub-cooled flow boiling water in vertical annular ducts heated by water.The duct widths are 5mm and 3mm,and the mass flux ranges are 16.8～55.3 kg/(m2.s) and15.3～62 kg/(m2.s),respectively.The results show that there exists a bubble layer near the wall,and most bubbles move in the layer.Most bubbles in 3mm annulus will slide for a distance not more than 2～3 times of the bubble diameter and keep expanding and shrinking for several times before departure.On the contrary,most bubbles in 5mm duct scarcely slide and are always bounced to the wall after departure.All these bubble behavior should be one of the reasons that the boiling can enhance heat transfer greatly.
出处
《核动力工程》
EI
CAS
CSCD
北大核心
2006年第z1期73-76,共4页
Nuclear Power Engineering
基金
哈尔滨工程大学基金项目(HEUF040126)
关键词
欠热流动沸腾
竖直环形流道
气泡行为
水加热
Sub-cooled flow boiling,Vertical annular duct,Bubble behavior,Water heating method
作者简介
孙立成(1973-),男,副教授.2005毕业于哈尔滨工程大学核能科学与工程专业,获博士学位.现主要从事反应堆热工水力研究. 阎昌琪(1955-),男,教授,博士生导师.1982毕业于哈尔滨船舶工程学院核动力装置专业,获硕士学位.现主要从事反应堆热工水力和强化传热技术研究. 孙中宁(1963-),男,教授.2000年毕业于哈尔滨工程大学轮机工程专业,获博士学位.现主要从事反应堆热工水力和热能工程研究.
