## 4 Conclusions  
In conclusion, a dehumidifier applied to a 10 kV AC outdoor box-type switchgear is studied, which uses dry air for internal circulation. The temperature, humidity, and flow field of the cable compartment inside the switchgear are simulated through CFD-EMAG coupling, and the dehumidification is analyzed through experimental verification with a self-made cable room. Based on the simulation results of the cable room's humidity, temperature, and velocity fields, optimization measures are proposed to achieve better dehumidification and anti-condensation of RMUs.  
Following are some conclusions that can be drawn:  
1. Based on mutual verification between simulation and experiment, the maximum relative errors of temperature, relative humidity, and velocity at the six monitoring  
Figure 12: (**a**) Temperature (K), (**b**) relative humidity, and (**c**) velocity (m/s) fields of layout 1 at Y = 50 mm cross-section when the humidity source is 100%.  
Figure 13: (**a**) Temperature (K), (**b**) relative humidity, and (**c**) velocity (m/s) fields of layout 4 at Y = 50 mm cross-section when the humidity source is 100%.  
points set in all layout experiments and simulations are only 3.61%, 7.14%, and 7.14%. Meanwhile, the average temperature relative error between experiment and simulation is 2.7% in the electric heating wire, and the errors are both within an acceptable range.
2. Based on mutual verification of experimental and simulation results, after optimizing the model, the overall dehumidification has the same trend. Layout 2 and Layout 4 have better dehumidification compared to the original layout. Layout 4 is the optimal layout. After reaching a steady state, compared with other layouts, the relative humidity of the corresponding measurement points is reduced by up to 10.6% with a minimum relative humidity of 45.1%; the dew point temperature can be reduced by up to 2.61 \({}^{\circ}\)C, with a minimum dew point temperature of 17.2 \({}^{\circ}\)C.
3. The new layout has a more uniform flow distribution compared to the original layout, with an overall temperature of around 301 K and a relative humidity of 50% on typical cross-sections. The overall distribution of flow velocity is also more uniform, with a maximum of no more than 0.3 m/s. Based on the above experiments and simulations, optimized dehumidification methods and measures have been proposed, providing support for their safe operation. However, this study is mainly based on the experimental environment of 28 \({}^{\circ}\)C and 50% humidity, which has certain limitations, and the bidirectional coupling of electric-thermal needs to be further considered. In the future, further research will be conducted based on more environmental conditions, providing more references for the prevention of condensation in RMU.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request. The authors of this paper are thankful for the support provided by [PERSON] from State Grid Hubei Electric Power Co., Ltd and Jingzhou Power Supply Company.  
The authors declare no conflict of interest.