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实验研究了Ｒ１３４ａ 在水平三维微肋管内的沸腾换热。实验段有效长度３ ．０ ｍ ，内径１２ｍｍ ，工质质量流率１００ ～２７７ ｋｇ／（ｍ２·ｓ） ，热负荷１０ ～２０ ｋＷ／ｍ２ ，饱和压力０．５４ ～０ ．６５ ＭＰａ．实验考察了质量流率，质量干度和饱和压力对换热系数的影响。这种三维内微肋管的换热特性同时与Ｗａｔｔｅｌｅｔ 关系式的预测值进行了比较，得到的换热强化因子在１ ．５ ～２ ．１ 之间。
The boiling heat transfer of R134a in horizontal three-dimensional microtube was experimentally studied. Effective length of experimental section 3. 0 m, the inner diameter of 12mm, working fluid mass flow rate of 100 ~ 277 kg / (m2 · s), heat load of 10 ~ 20 kW / m2, saturation pressure of 0.54 ~ 0. 65 MPa. The effects of mass flow rate, mass dryness and saturation pressure on the heat transfer coefficient were investigated experimentally. The heat transfer characteristics of the three-dimensional micro-finned tube are also compared with the predictions of Wattelet’s relation, and the heat transfer enhancement factor obtained is 1. 5 ~ 2. 1 between.