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在蒸发温度为5~15℃，工质质量流速变化范围为50~500 kg/(m2?s)，热流密度范围为5~25 kW/m2和干度范围为0.01~0.9的条件下，对R134a在卧式螺旋管内沸腾两相流型及壁温特性进行了实验研究。利用可视化技术对流型进行了观察分析，发现在相同工况条件下，卧式螺旋管上升段和下降段的流型有所不同，特别是形成环状流之前存在明显不同的过渡流型，分别为“波环状流型”和“超大气弹流型”，因此，对上升段和下降段分别建立了流型图。分别获得了卧式螺旋管沿管长和沿螺旋管横截面圆周方向的壁面温度分布特性。壁面温度沿管长呈逐渐降低的趋势；沿横截面圆周方向，最外侧壁温最低，最内侧壁温最高，两侧温度居中。“,”This paper presented an experimental investigation on flow boiling patterns and wall temperatures of R134a in horizontal helically-coiled pipe. The experiments were carried out at saturation temperature from 5 to 15℃, with the refrigerant mass flux varying from 50 to 500 kg/(m2?s), heat flux varying from 5 to 25 kW/m2, and the vapor quality ranging from 0.01 to 0.9. Through visualization experiment, it can be found that the flow patterns in the rising and declining sections are different under the same conditions. The transition flow patterns before the annular flow are obviously different, which are “wave annular flow” and “super slug flow”, so two different flow pattern figures were proposed for the rising and declining sections, respectively. The wall temperature distribution during flow boiling was experimentally determined. The results show that the wall temperature gradually decreased along the tube; along the cross-section circumference, the outside temperature of the cross section is the lowest, and the inside temperature is the highest.