Energy Storage Science and Technology ›› 2024, Vol. 13 ›› Issue (8): 2605-2614.doi: 10.19799/j.cnki.2095-4239.2024.0238

• Energy Storage Materials and Devices • Previous Articles     Next Articles

Study on supercritical nitrogen flow and heat transfer characteristics in a vertical corrugated channel

Pengyu LI1,2,3,4(), Xipeng LIN1, Liang WANG1, Haisheng CHEN1(), Yifei WANG5()   

  1. 1.Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2.University of Chinese Academy of Sciences, Beijing 100049, China
    3.Zhongke Nanjing Institute of Future Energy System
    4.University of Chinese Academy of Sciences, Nanjing 211135, Jiangsu, China
    5.National Energy Large Scale Physical Energy Storage Technologies R&D Center of Bijie High-tech Industrial Development Zone, Bijie 551700, Guizhou, China
  • Received:2024-03-19 Revised:2024-05-07 Online:2024-08-28 Published:2024-08-15
  • Contact: Haisheng CHEN, Yifei WANG E-mail:lipengyu@iet.cn;chen_hs@mail.etp.ac.cn;wangyifei@iet.cn

Abstract:

This paper examines the effects of different mass flow rates [G = 200—400 kg/(m2·s)], heat fluxes (q = 200—400 kW/m2), and system pressures (P = 5—7 MPa) on the flow and heat transfer characteristics of supercritical nitrogen in a vertical corrugated channel. The local heat transfer distribution characteristics and periodic average convective heat transfer coefficients are analyzed. The primary reasons for the differences between the vertical flow directions are analyzed using the field synergy principle and the buoyancy effect. The results show that the local heat transfer coefficient is unevenly distributed and fluctuates in the period. The periodic mean heat transfer coefficient better reflects the overall flow heat transfer characteristics of supercritical nitrogen in the flow channel. Increasing the mass flow rate can significantly enhance the heat transfer and weaken the influence of the flow direction on the heat transfer coefficient. Increasing the heat flux decreases the heat transfer coefficient in the flow channel and strengthens the influence of the flow direction on the heat transfer coefficient. When the system pressure is close to critical, the peak value of the heat transfer coefficient in the flow channel increases, and the differences in the heat transfer coefficients in different flow directions are slightly affected by the system pressure. The difference in the convective heat transfer coefficient in different flow directions in a corrugated channel is primarily caused by the buoyancy and field synergy effects.

Key words: compressed air energy storage, supercritical nitrogen, cold storage, corrugated channel, field synergy

CLC Number: