An experimental study on heat transfer of CO2 solid-gas two phase flow with dry ice sublimation
An experimental study on heat transfer of CO2 solid-gas two phase flow with dry ice sublimation
复制标题
CO2固气两相流干冰升华传热实验研究
DOI：
10.1016/j.ijthermalsci.2011.05.019
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发表时间：
2011-11-01
影响因子：
4.5
通讯作者：
Yamaguchi, Hiroshi
中科院分区：
文献类型：
--
作者：
Zhang, Xin-Rong;Yamaguchi, Hiroshi
了解CO2固气两相流的换热特性，对设计新型制冷系统具有重要意义。为了测量CO2气固两相流体的换热性能，需要对其进行闭环系统的连续测量。本文设计、建造和测试了一套实验装置，用于测量CO2固气两相流的温度、压力，并进一步研究其传热特性。作为调查的第一步，测量工作在水平圆管中进行。根据所获得的结果，验证了本实验装置能够连续获得CO2气固两相流体在闭环系统中的流动，并且可以进行换热测量。结果表明，实验测得的对流换热系数平均值为310W/(m(2)K)，高于气流对流换热系数的平均值。在升华区，努塞尔数沿管长方向增大。此外，本研究还对CO2固体气流的换热特性有了一定的认识。(C)2011年爱思唯尔·马森公司。版权所有。
Knowledge on heat transfer characteristics of CO2 solid-gas two phase flow is important to design of some new refrigeration systems. Continuously obtaining CO2 solid gas fluid flow in a closed loop is necessary to measure its heat transfer. In this paper, an experiment set-up is designed, constructed and tested in order to measure the temperatures, pressures of the CO2 solid gas two phase flow, and also further its heat transfer characteristics. As the first step of the investigation, the measurement work is conducted in a horizontal circular tube. Based on the obtained results, it is verified the present experiment set-up can continuously obtain CO2 solid gas fluid flow in the closed loop and also heat transfer measurement is possible. The results show an average value 310 W/(m(2) K) of heat convective coefficient is experimentally obtained in the present range, which is higher than that of gas flow. The Nusselt number is found to increase along the tube length in the sublimation area. In addition, some knowledge on the heat transfer characteristic of the CO2 solid gas flow is learned from the present study. (C) 2011 Elsevier Masson SAS. All rights reserved.