## 6 Discussion and Conclusions  
In this paper, a multiscale WRF-CFD-FEM numerical framework is developed to analyze the motions of the transmission line subjected to coupled wind and rain loads during typhoon events. A case study was presented in detail by solving the dynamic responses of a full-scale transmission line located in Zhoushan Island during Super Typhoon Lekima in 2019. The proposed framework firstly reproduced the evolution of Super Typhoon Lekima, including the wind field and precipitation distribution at the coastal area using mesoscale weather model WRF. Then, the coupled wind and rain fields around the transmission line were simulated by the Eulerian multiphase CFD model. Finally, the motion of the conductor under joint actions of wind and rain, i.e., WDR loads, were solved by the finite element method. Some conclusions are summarized as follows:  
1. The ARW model is capable of simulating the track and intensity evolution of typhoon events. It can also explicitly resolve the typhoon wind field and the associated precipitation for a target region. The simulated wind and rain results of Super Typhoon Lekima show good agreements with observations.
2. The coupled effect of wind and rain load consists of the upper rivulet attached to the conductor surface and the direct impingement of raindrops. The simulated drag and lift coefficients of the overhead conductor under WDR conditions exhibit noticeable variations with the wind angle of attack.
3. The proposed multiscale WRF-CFD-FEM numerical framework could be used to analyze and predict the dynamic responses of transmission lines under typhoon conditions by considering coupled wind and rain effects. In the case study of Super Typhoon Lekima, the horizontal displacements of the transmission line under the coupling of wind and rain are significantly larger than those of wind loads only. The increasing rates of 17-18% were found for the mean displacements under WDR loads compared to the wind loads. It is also found that WDR would produce larger conductor tension to the supporting tower than only wind condition. Such larger swing behavior of the overhead conductor due to WDR loads indicates the importance of coupled effects of wind and rain during typhoon conditions for the design of transmission lines.  
Conceptualization, J.S. and M.H.; methodology, J.S.; software, J.S.; validation, S.L.; formal analysis, J.S.; investigation, J.S. and S.L.; resources, M.H.; data curation, J.S. and S.L.; writing--original draft preparation, J.S.; writing--review and editing, M.H. and S.L.; visualization, J.S.; supervision, M.H.; project administration, M.H. and W.L.; funding acquisition, M.H. and W.L. All authors have read and agreed to the published version of the manuscript.  
Supports for this research are provided by Natural Science Foundation of Zhejiang Province (Project No. LZ22E080006), National Natural Science Foundation of China (Project No. 52178512) and Ningbo Key R&D Program (Project No. 2023Z221).  
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**Funding:** Supports for this research are provided by Natural Science Foundation of Zhejiang Province (Project No. LZ22E080006), National Natural Science Foundation of China (Project No. 52178512) and Ningbo Key R&D Program (Project No. 2023Z221).
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Some or all data, models, or codes that support the findings of this study are available from the corresponding author upon reasonable request.  
**Conflicts of Interest:** The authors declare no conflicts of interest.