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过程工程学报 ›› 2021, Vol. 21 ›› Issue (10): 1167-1176.DOI: 10.12034/j.issn.1009-606X.220336

• 流动与传递 • 上一篇    下一篇

重油燃烧器Y型喷嘴气液两相流动与雾化特性模拟

王志奇*， 陈柳明， 肖炳英， 谢宝琦   

  1. 湘潭大学机械工程学院，湖南 湘潭 411105

  • 收稿日期:2020-10-14 修回日期:2020-12-06 出版日期:2021-10-28 发布日期:2021-10-26
  • 通讯作者: 王志奇 wangzhiqi@xtu.edu.cn
  • 基金资助:
    湖南省自然科学基金

Simulation of gas-liquid two-phase flow and atomization characteristics of Y-type nozzle for heavy oil burner

Zhiqi WANG*,  Liuming CHEN,  Bingying XIAO,  Baoqi XIE   

  1. Institute of Mechanical Engineering, Xiangtan University, Xiangtan, Hunan 411105, China

  • Received:2020-10-14 Revised:2020-12-06 Online:2021-10-28 Published:2021-10-26
  • Contact: WANG zhizhi qi wangzhiqi@xtu.edu.cn

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摘要： 为改善重油雾化质量，针对沥青站重油燃烧器Y型喷嘴，运用CFD (Computational Fluid Dynamics)方法研究了喷嘴结构参数(混合室长度、入口直径比、入口夹角)与雾化参数(重油流量、空气入口压力、重油温度)对喷嘴气液两相流动与雾化特性的影响。结果表明，结构参数与雾化参数直接影响喷嘴内油膜厚度与气液两相速度差；不同参数下，喷嘴气耗率与液滴索泰尔平均直径的变化规律相反；综合考虑两个雾化性能指标，混合室的适宜长度为15~20 mm，入口夹角的合理范围为60°~75°，入口最佳直径比为1.0~1.1；为保证重油获得较好的雾化效果，空气入口压力应大于0.5 MPa，这为优化Y型雾化喷嘴的结构与运行参数提供了参考。

关键词: 重油雾化, 数值模拟, Y型喷嘴, 两相流动, 雾化特性

Abstract: Heavy oil burner is the key component of asphalt mixing equipment. However, heavy oil is not easy to atomize due to its high viscosity and surface tension, which results in low combustion efficiency and high pollutant discharge in heavy oil burners. Y-type atomizing nozzle is widely used in heavy oil atomization because of its simple structure and wide adjustment range. A large number of experiments and simulations were carried out on the atomization characteristics of heavy oil. However, the existing research only analyzed the atomization characteristics from the aspects of structure or atomization parameters, ignoring the gas-liquid two-phase flow characteristics in the nozzle. Therefore, the research on the gas-liquid two-phase flow and atomization characteristics of Y-type atomizing nozzle has an important guiding role in the design of heavy oil burner. In order to improve the quality of heavy oil atomization, computational fluid dynamics software were used to explore the influence of nozzle structure parameters (mixing chamber length, inlet diameter ratio, angle between air and fuel inlet) and atomization parameters (mass flow rate of oil, air inlet pressure, temperature of oil) on the gas-liquid two-phase flow and heavy oil atomization characteristics of Y-type nozzle. The results showed that the structure parameters and atomization parameters directly affected the oil film thickness and gas-liquid two-phase velocity difference in the nozzle. Under different parameters, the change rule of gas-liquid rate and droplet Sauter mean diameter was opposite. Considering the two atomization performance indexes, the optimal length of mixing chamber was 15~20 mm, the reasonable range of inlet angle was 60°~75° and the optimal inlet diameter ratio was 1.0~1.1. In order to ensure the better atomization effect of heavy oil, the air inlet pressure should be greater than 0.5 MPa, the above parameters obtained by simulation provide guidance for the structure optimization design and operation parameter setting of Y-type nozzle.

Key words: heavy oil atomization, numerical simulation, Y-type nozzle, two-phase flow, atomization characteristics