摘要
为了提高真空相变加热炉换热管外蒸汽膜状凝结换热效果,引入微振动激励打破管外覆凝结液膜的受力平衡,促进液膜快速脱落。运用Fluent动态网格技术,对在简谐振动作用下单圆管外覆凝结液膜脱落的运动特性进行模拟研究,分析了振动参数对管外液膜覆盖率的影响。结果表明:与静止圆管相比,振动圆管具有更薄且扰动更剧烈的边界层,并发生交替斜向绕流,加强了对液膜的破坏作用;振动大大加快了外覆凝结液膜的脱落,施加微振动后圆管外覆凝结液膜开始破口时间远远快于静态下的106 ms,且凝结液膜脱落时效随着振幅和频率的增大而加快。研究成果的应用可以大大提高真空相变加热炉的加热效率。
In order to improve the heat transfer effect of steam film condensation outside the heat exchange tube of vacuum phase-change heating furnace, the micro-vibration excitation is introduced to break the force balance of condensate film on the external surface of the heat exchange tube so as to promote the quick detaching of liquid film. In this paper, the dynamic characteristics of the liquid film detaching from the external surface of single circular tube under the effect of simple harmonic oscillation were simulated by using the dynamic grid software FLUENT. Then, the effects of the vibration parameters on the coverage rate of liquid film around the tube were analyzed. It is indicated that the vibrating circular tube is superior to the still circular tube, for its boundary layer is thinner with stronger vibration and the alternative oblique bypass appears, strengthening the damage to the liquid film. The vibration also accelerates dramatically the detaching of liquid film condensed on the external surface. After micro-vibration is applied to the liquid film condensed on the external surface of tube, the liquid film breaching time is much shorter than that（i.e., 106 ms） in the static state. Furthermore, the time efficiency of the detaching of condensate liquid film is increased with the increase of vibration amplitude and frequency. In conclusion, the application of the research results can improve the heating efficiency of vacuum phase-change heating furnace significantly.
作者
王海琴
李伟
张雷
张足斌
WANG Haiqin;LI Wei;ZHANG Lei;ZHANG Zubin(China University of Petroleum（East China;Shandong Key Laboratory of Oil ＆ Gas Storage and Transportation Safety;Oil ＆ Gas Storage and Transportation Company,Xinjiang Oilfield Company)
出处
《油气储运》
CAS
北大核心
2018年第7期790-797,共8页
Oil & Gas Storage and Transportation
基金
国家自然科学基金"海上天然气净化脱CO2过程吸附/脱附特性研究"
51306210
关键词
真空相变加热炉
微振动
斜向绕流
膜状凝结
液膜脱落
动态特性
vacuum phase-change heating furnace
micro-vibration
oblique bypass
film condensation
liquid filmdetaching
dynamic characteristics
