摘要
随着第四代核能系统的研发,使用高效、安全、经济的超临界二氧化碳作为冷却剂或二回路能量转换工质的反应堆成为研究热点。管壳式换热器具有制造维护简单、流动压降小的特点,在超临界二氧化碳对流换热中具有一定的应用前景。本文使用数值模拟方法研究了超临界二氧化碳横掠管束对流换热特性。结果表明:超临界二氧化碳横掠管束是周期性流动,拟临界区的超临界二氧化碳横掠管束流动换热不同于远离拟临界点的超临界区。Zukauskas关联式适用于远离拟临界点的超临界区对流换热Nu计算,不适用于拟临界区Nu计算。本文对Zukauskas关联式在拟临界区进行了修正,修正后的公式适用于7.5 MPa下主流温度300～310 K的拟临界区Nu计算,最大误差为21.40%。
With the development of the 4^th generation nuclear power system, reactors using efficient, safe and economical supereritieal carbon dioxide as coolant or working fluid of the second loop have become a research hotspot. The tube and shell heat exchanger has the characteristics of easy manufacture, easy maintenance and low flow pressure drop, which has a good application prospect in heat transfer of supereritical carbon dioxide. The heat transfer characteristics of supercritieal carbon dioxide was numerically simulated. supercritical carbon dioxide is a periodic flow It is shown that the cross flow over tube bundles of The flow and heat transfer characteristic in the pseudo region is different from that in the supercritical region which is far from the critical point. Zukauskas correlation is applicable to calculate Nu in the supercritical region when it is far from the critical point, while it is not applicable to the pseudo critical region. Zukauskas correlation is modified for tile pseudo critical region, and it can be applied to the near critical region with a pressure of 7.5 MPa and a mainstream temperature of 300-310 K. The maximum error is 21.40%.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2017年第12期2658-2664,共7页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.51576103)
