SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (11): 2746-2757.DOI: 10.1016/j.cjche.2020.07.001

• Fluid Dynamics and Transport Phenomena • Previous Articles     Next Articles

A 2D numerical study on the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures on a vertical plate

Lili Zhang, Guanmin Zhang, Yi Zhang, Maocheng Tian, Jingzhi Zhang   

  1. School of Energy and Power Engineering, Shandong University, Jinan 250061, China
  • Received:2019-11-27 Revised:2020-06-24 Online:2020-12-31 Published:2020-11-28
  • Contact: Guanmin Zhang
  • Supported by:
    The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 51576115), the Shandong Provincial Natural Science Foundation of China (No. ZR2018BEE026), the China Postdoctoral Science Foundation (No. 2018M642655) and the Fundamental Research Funds of Shandong University of China (No. 2017GN0026).

A 2D numerical study on the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures on a vertical plate

Lili Zhang, Guanmin Zhang, Yi Zhang, Maocheng Tian, Jingzhi Zhang   

  1. School of Energy and Power Engineering, Shandong University, Jinan 250061, China
  • 通讯作者: Guanmin Zhang
  • 基金资助:
    The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 51576115), the Shandong Provincial Natural Science Foundation of China (No. ZR2018BEE026), the China Postdoctoral Science Foundation (No. 2018M642655) and the Fundamental Research Funds of Shandong University of China (No. 2017GN0026).

Abstract: To improve the transportation efficiency and reduce the supply cost, the liquefaction becomes an important technology to store and transport the natural gas. During the liquefaction, the various components (e.g. propane, ethane, methane etc.) undergo fractional condensation phenomenon due to their different boiling points. This means that when one component condenses, others play a role of non-condensable gas (NCG). In order to reveal the influence mechanism of NCG on this condensation process, a numerical method was employed in this paper to study the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures, namely the propane/methane (80%-95%), ethane/methane (65%-85%) and methane/nitrogen (2%-13%) mixtures, on a vertical plate. The model was proposed based on the diffusion layer model, and the finite volume method was used to solve the governing equations. A user defined function was developed by cell iterative method to obtain the source terms in the condensation process. The numerical results show that the gas phase boundary layer formed by the NCG becomes the main resistance to the reduction of heat transfer coefficient. And for the above three mixtures, there is a negative correlation between the NCG concentration and the heat transfer coefficient. Meanwhile, the results show a good agreement with the experimental data, meaning that the proposed model is reliable. Three mixtures within same non-condensable mole fraction of 20% were also investigated, indicating that the mixtures with a higher binary hydrocarbon molecular ratio have a lower heat transfer coefficient. As a result, the presence of the lighter NCG contributes to a thicker boundary layer.

Key words: Condensation characteristics, Non-azeotropic hydrocarbon mixtures, Heat and mass transfer, Liquid film distribution, Vertical plate

摘要: To improve the transportation efficiency and reduce the supply cost, the liquefaction becomes an important technology to store and transport the natural gas. During the liquefaction, the various components (e.g. propane, ethane, methane etc.) undergo fractional condensation phenomenon due to their different boiling points. This means that when one component condenses, others play a role of non-condensable gas (NCG). In order to reveal the influence mechanism of NCG on this condensation process, a numerical method was employed in this paper to study the condensation characteristics of three non-azeotropic binary hydrocarbon vapor mixtures, namely the propane/methane (80%-95%), ethane/methane (65%-85%) and methane/nitrogen (2%-13%) mixtures, on a vertical plate. The model was proposed based on the diffusion layer model, and the finite volume method was used to solve the governing equations. A user defined function was developed by cell iterative method to obtain the source terms in the condensation process. The numerical results show that the gas phase boundary layer formed by the NCG becomes the main resistance to the reduction of heat transfer coefficient. And for the above three mixtures, there is a negative correlation between the NCG concentration and the heat transfer coefficient. Meanwhile, the results show a good agreement with the experimental data, meaning that the proposed model is reliable. Three mixtures within same non-condensable mole fraction of 20% were also investigated, indicating that the mixtures with a higher binary hydrocarbon molecular ratio have a lower heat transfer coefficient. As a result, the presence of the lighter NCG contributes to a thicker boundary layer.

关键词: Condensation characteristics, Non-azeotropic hydrocarbon mixtures, Heat and mass transfer, Liquid film distribution, Vertical plate