Numerical Study of Spacer Effects on Convective Heat Transfer at Low Flow Rates

Ding Guanqun; Xiao Yao; Gao Xinli; Liu Bo; Li Junlong; Gu Hanyang

doi:10.13832/j.jnpe.2022.06.0008

Volume 43 Issue 6

Dec. 2022

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Ding Guanqun, Xiao Yao, Gao Xinli, Liu Bo, Li Junlong, Gu Hanyang. Numerical Study of Spacer Effects on Convective Heat Transfer at Low Flow Rates[J]. Nuclear Power Engineering, 2022, 43(6): 8-14. doi: 10.13832/j.jnpe.2022.06.0008

Citation:

Ding Guanqun, Xiao Yao, Gao Xinli, Liu Bo, Li Junlong, Gu Hanyang. Numerical Study of Spacer Effects on Convective Heat Transfer at Low Flow Rates[J]. Nuclear Power Engineering, 2022, 43(6): 8-14. doi: 10.13832/j.jnpe.2022.06.0008

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Numerical Study of Spacer Effects on Convective Heat Transfer at Low Flow Rates

doi: 10.13832/j.jnpe.2022.06.0008

1.
School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
2.
Nuclear and Radiation Safety Center, Ministry of Ecology and Environment, Beijing, 102488, China

Received Date: 2021-11-19
Rev Recd Date: 2022-02-23
Publish Date: 2022-12-14

Abstract

Abstract

A numerical study is carried out for the thermal-hydraulic characteristics of a circular tube with spacer at low flow rates and high heat flux. The convective heat transfer of single-phase water in a smooth circular tube at low flow rates and the spacer effects are calibrated by the empirical correlation and experimental data. A CFD method based on the SST k-ω model is established. The simulation results show that the heat transfer characteristics downstream of the spacer depend on the buoyancy lift parameter. For the forced convection zone and mixed convection heat transfer decreasing zone, the heat transfer downstream of the spacer is always enhanced and the Nussel number decays exponentially. For the mixed convection heat transfer recovery zone and natural convection zone, due to the coupling effect of flow field and heat transfer, the heat transfer downstream of the spacer deteriorates and the Nussel number oscillates with damping. The influence range of heat transfer at the downstream of the spacer first increases and then decreases with the increase of buoyancy lift parameters. The larger the spacer blocking ratio is, the more severe the heat transfer oscillation is, and the worse the heat transfer caused by the spacer is. This study can provide a reference for the design of core in a low-flow core.
- Spacer effects,
- Buoyancy lift parameter,
- Mixed convection,
- Damped oscillation,
- Blocking ratio,
- Heat transfer deterioration

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References(20)

References

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