高效单旋式换热器入口分布器气液混合数值研究
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摘要
在高效单旋式换热器中,当气液介质分别进入设备时,其入口分布器的合理设置意义重大,两相流混合均匀与否将直接影响换热管中流体的均匀分配及传热效率。根据工程实践中的操作工况,采用计算流体动力学(CFD)仿真技术对换热器一种入口分布器内的流体流动状况进行数值模拟,并在此基础上进行深入分析。结果表明,多孔筛板对于气相均布起到关键作用,但由于密度差异所引起的自然对流,出口截面处液相主要靠近外侧区域分布,中心管区域分布较少,气液混合有待进一步优化。此外,对复杂结构入口分布器的数值模拟,可为相关产品的结构优化提供一定的指导意义。
In the high-efficiency spiral tube heat exchanger(STHE), when gas-liquid flow enters the equipment separately, the reasonable setting of entrance distributor is of great significance, and the uniform mixing of two-phase flow will directly affect the fluid distribution and the heat transfer efficiency. According to the operating conditions in engineering practice, the computational fluid dynamics(CFD) technology is used to numerically simulate the fluid flow in an entrance distributor of STHE, and a thorough analysis is made. The results show that the porous plate plays a key role in the uniform distribution of the gas phase. However, due to the natural convection caused by the density difference, the liquid phase at the outlet section is mainly distributed in the outer section, and less in the section close to central pipe. It means that the gas-liquid mixing needs to be further optimized. In addition, the numerical simulation of entrance distributor with complex structure contributes to provide guidance for the structure optimization of related products.
In the high-efficiency spiral tube heat exchanger(STHE), when gas-liquid flow enters the equipment separately, the reasonable setting of entrance distributor is of great significance, and the uniform mixing of two-phase flow will directly affect the fluid distribution and the heat transfer efficiency. According to the operating conditions in engineering practice, the computational fluid dynamics(CFD) technology is used to numerically simulate the fluid flow in an entrance distributor of STHE, and a thorough analysis is made. The results show that the porous plate plays a key role in the uniform distribution of the gas phase. However, due to the natural convection caused by the density difference, the liquid phase at the outlet section is mainly distributed in the outer section, and less in the section close to central pipe. It means that the gas-liquid mixing needs to be further optimized. In addition, the numerical simulation of entrance distributor with complex structure contributes to provide guidance for the structure optimization of related products.
引文
[1]刘江. ANSYS 14.5 Workbench机械仿真实例讲解[M].北京:机械工业出版社, 2015.
[2]贝尔J.多孔介质流体力学[M].李竞生,陈崇希,译.北京:中国建筑工业出版社, 1983.
[3]谢龙汉,赵新宇. ANSYS CFX流体分析及仿真[M].北京:电子工业出版社, 2013.
[2]贝尔J.多孔介质流体力学[M].李竞生,陈崇希,译.北京:中国建筑工业出版社, 1983.
[3]谢龙汉,赵新宇. ANSYS CFX流体分析及仿真[M].北京:电子工业出版社, 2013.