中文摘要：

为探索低潜热工质在卧式螺旋管内流动沸腾的临界热流密度（CHF）特性,采取大电流直接对实验段通电,利用不锈钢电阻加热的方式,在出口压力p=0.40~1.05 MPa,质量流速G=51~257 kg/m2s,入口热平衡干度Xi=-0.18~0.43的条件下开展了R134a在卧式螺旋管内流动沸腾的CHF特性研究。实验用螺旋管内径7.6 mm,螺旋径300 mm,节距40 mm,有效加热长度7.07 m。重点分析了实验段壁温沿管长和管截面周向的变化规律,以及压力、流量、干度等参数对CHF值的影响,并把实验数据与Bowring和Shah关联式的计算值进行了验证比较,结果发现这2种关联式在该实验条件下均不适用。

英文摘要：

An experimental study of critical heat flux（CHF） using R134a as work fluid in horizontal helically-coiled tubes was performed to investigate the CHF characteristics.The stainless steel test section was directly heated uniformly by high-power source.The experiment parameters were： a.outlet pressures of 0.40～1.05 MPa,b.mass fluxes of 51～257 kg/m2s,and c.inlet qualities of-0.18～0.43.And the structure parameters of the test section were： inner diameter of 7.6mm,helix diameter of 300 mm,helix pitch of 40 mm and heated length of 7.07 m.The characteristics of wall temperature and the effects of pressure,mass flux and vapor qualities on CHF were investigated and discussed in this paper.Experiment data were compared with the calculated results by Bowring correlation and Shah correlation,respectively.It was found that the two correlations were not suitable for predicting CHF under the present experiment conditions.