强化传热管束狭窄空间内R_11的沸腾换热特性

对紧凑型滚压面传热管管束狭窄空间内R－11的沸腾强化换热进行了实验研究，确认了由紧凑型滚压强化管束组成的满液式蒸发换热器具有良好的换热性能。其原理是利用强化传热管管束狭窄空间提前从自然对流换热转换为旺盛核沸腾换热，实验结果确认了管束形成的狭窄空间和强化传热面两种强化技术对沸腾换热的强化效果不能简单叠加。

Boiling Heat Exchange Characteristics of R-11 in the Narrow Spaces of an Intensified Heat-transfer Tube Bank

An experimental investigation was conducted of the intensified boiling heat transfer of R 11 in the narrow spaces of a compact heat transfer tube bank consisting of rolled surfaces. The results of the investigation confirm that the full liquid type of evaporative heat transfer device comprising the above cited tube bank offers a good heat transfer performance. Its working principle is based on the utilization of the narrow spaces of the intensified heat transfer tube bank for an early conversion of natural convection heat transfer into a thriving nucleate boiling heat transfer. The experimental results also confirm that the boiling heat transfer intensification effect of the two kinds of intensified techniques as offered by 1) the narrow spaces formed by the tube bank and 2) the intensified heat transfer surfaces should not be viewed as a version of simple superimposition.