R134a was recognized as probably one of the most important refrigerants of the two past decades. Among the proposed alternative fluids, there are certainly isobutane (R600a) and R152a. This article presents about 200 new heat transfer coefficient and pressure drop data obtained during flow boiling of R152a and R600a inside a smooth copper tube having an internal diameter of 4 mm. Three saturation temperatures were considered for each refrigerant, from 5 °C to 20 °C. Furthermore, for each temperature studied, the heat flux was varied between 15 and 30 kW m⁻² and the refrigerant mass flux from 100 to 400 kg m⁻² s⁻¹. After presenting the new data, a critical comparison was proposed between the performance of these refrigerants and R134a. Finally, some classic correlations available in the literature have been implemented. The deviations between the calculated and experimental values were reported and commented.

R134a可能被认为是过去两个十年中最重要的制冷剂之一。在提出的替代流体中，当然有异丁烷（R600a）和R152a。本文介绍了内径为4 mm的光滑铜管内R152a和R600a流动沸腾期间获得的约200个新的传热系数和压降数据。每种制冷剂考虑了三个饱和温度，从5°C到20°C。此外，对于每个研究温度，热通量在15至30 kW m ^-2之间变化，制冷剂质量通量在100至400 kg m ^-2  s ^{-1之间变化}。在提供新数据之后，提出了对这些制冷剂和R134a的性能进行严格的比较。最后，已经实现了文献中一些经典的相关性。报告和评论计算值与实验值之间的偏差。