The present paper concerns an experimental investigation about the heat transfer coefficient during convective condensation of hydrocarbons and their zeotropic mixtures. Experiments were performed in a horizontal smooth channel, with internal diameter of 9.43 mm for R600a, R290, R1270, R600a/R290 (70/30 molar fraction) and R600a/R1270 (75/25 molar fraction), for mass velocities ranging from 50 to 250 kg m⁻² s⁻¹, vapor qualities from unity to zero, heat fluxes from 5 to 60 kW m⁻² and a saturation temperature of 35°C. Experiments were also performed for R134a. In general, higher heat transfer coefficients were obtained for the hydrocarbons compared to R134a. The heat transfer process was dominated by shear effects for the hydrocarbons regardless of the mass velocity. At low mass velocities (below 100 kg m⁻² s⁻¹), both mixtures provided lower heat transfer coefficients than the pure fluids. At high mass velocities a reduction of the heat transfer coefficient compared to the pure fluid was noticed only for R600a/R1270 at high qualities. The experimental data is compared against prediction methods from literature and based on the pure fluids database, a new strictly empirical prediction method is proposed, which performs better for both pure fluids and mixtures database. For the mixtures, the performance of the methods was improved when considering a correction for the mass transfer effects associated to the concentration gradients near the liquid/vapor interface.

本文件涉及对烃类和它们的非共沸混合物的对流凝结期间的热传递系数的实验研究。实验是在水平的平滑信道执行，以9.43毫米的R600a，R290，R1270，R600a的/ R290（70/30摩尔分数）和R600a的/ R1270（75/25摩尔分数）内的直径，质量速度范围从50 250公斤米^-2小号^-1，蒸汽质量，从统一到零，热通量从5至60千瓦米^-2和35℃的饱和温度。实验还为R134a的执行。一般地，对于相比于R134a的烃获得较高的传热系数。无论质量速度如何，传热过程都由烃的剪切效应主导。在低质量速度（低于100公斤米^-2小号^-1)，两种混合物的传热系数都低于纯流体。与纯流体相比，在高质量速度下，仅在高质量的 R600a/R1270 中注意到传热系数降低。将实验数据与文献预测方法进行比较，并基于纯流体数据库，提出了一种新的严格经验预测方法，该方法对纯流体和混合物数据库都具有更好的性能。对于混合物，当考虑对与液体/蒸汽界面附近的浓度梯度相关的传质效应进行校正时，方法的性能得到了改进。