## 6 Conclusions  
This paper presents the results of hydrodynamic tests conducted on a submerged radial gate at a high-head flood discharge outlet. Initially, a hydraulic model test with a scale ratio of 1:25 was conducted to study the fluctuating pressure distribution on the gate panel under different opening conditions. Then, using the ICEEMDAN-HHT theory, the characteristics and causes of the fluctuating pressure on the panel were systematically analyzed. Furthermore, a deep learning method, ICEEMDAN-SSA-LSTM, was employed to predict the fluctuating pressure on the gate panel. The following conclusions were drawn:  
1. The load acting on the gate panel is primarily time averaged, with the RMS of fluctuating pressure constituting less than 10% of the time-average pressure. The RMS of fluctuating pressure near the bottom is significantly higher than that in the middle and top of the gate, while the time-average pressure in the middle is higher than that at the bottom and top of the gate. It is noteworthy that there is a notable disparity between the distribution of fluctuating pressure and hydrostatic pressure at the gate.
2. Decomposing the fluctuating pressure signal of the gate panel reveals that the time-domain data of water fluctuating pressure are weakly non-stationary but can be considered stationary to some extent. Based on this, applying the improved Hilbert transform to each IMF component yields different frequency-band components, which can be interpreted as a decomposition of turbulent water flow into vortices at various scales. Moreover, the modal aliasing of fluctuating pressures of each component indicates that the turbulent vortex structure contains multi-scale vortices, whose random diffusion and mixing collectively contribute to the turbulent behavior of the flow.
3. A fluctuating pressure prediction method based on ICEEMDAN-SSA-LSTM was proposed to improve the accuracy of the gate panel fluctuating pressure signal compared to the LSTM and ICEEMDAN-LSTM prediction methods. This method can provide technical support for subsequent gate vibration signal detection and fault diagnosis.  
Conceptualization, X.L. and Y.L. ([PERSON]); methodology, X.L., S.T. and W.B.; software, X.L. and Y.L.([PERSON]); validation, X.L., W.B. and X.Z.; formal analysis, W.B. and X.Z.; investigation, W.B.; resources, Y.L. ([PERSON]) and S.T.; data curation, X.L.; writing--original draft preparation, X.L.; writing--review and editing, Y.L. ([PERSON]); visualization, Y.L. ([PERSON]); supervision, S.T. and Y.L. ([PERSON]); project administration, S.T. and Y.L. ([PERSON]); funding acquisition, S.T. and Y.L. ([PERSON]). All authors have read and agreed to the published version of the manuscript.  
This research was funded by Science and Technology Projects of CHINA HUANENG GROUP (grant No. HNKJ22-H108), Science and Technology Projects of China Power Construction Corporation Limited (grant No. DJ-ZDXM-2021-03), and the National Natural Science Foundation of China (grant No. 52179060).  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
Authors [PERSON], [PERSON] and [PERSON] were employed by the company Power China Guiyang Engineering Corporation Limited. The remaining authors declare that the re-search was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.