## 3 Experimental Results and Simulation Analysis  
### Experimental Conditions  
The laboratory was kept at a room temperature of 28 \({}^{\circ}\)C, and the humidity was controlled at 50% for the experiment. A 1.0 mm diameter electric heating wire was placed vertically inside the cable room for temperature field research. Based on the simplified cable room model, a 630 A current excitation is applied to three individual cables, resulting in thermal powers of 4.98 W, 4.94 W, and 4.98 W, totaling 14.88 W. In total, 4.94 W of power was applied to the middle cable of the electric heating wire through a voltage regulator. When the cable room door was kept closed, the average temperature of the electric heating wire, as measured by the K-type thermocouple, was 100 \({}^{\circ}\)C. Figure 5a shows the initial experimental cable compartment and related equipment during the preliminary experiment. On this basis, two ventilating pipes were added, doubled in length for better measurement, and a dehumidifier was placed in front of the air supply pipeline, as shown in Figure 5b. The positions of the experiments corresponding to the above six points are depicted in Figure 6a. Moreover, as shown in Figure 6b, after doubling the length of the pipes, a hole was opened in the middle to facilitate the measurement and verification of inlet and outlet velocity values, such as G, H, I, and J.  
Figure 4: (**a**) The velocity variation trend of different grid monitoring points in the cable room model with electric heat wire of the verification experiment; (**b**) the velocity variation trend of different grid monitoring points in the cable room model with cables. Figure 5: (**a**) Diagram of the initial experimental cable room and related experimental equipment; (**b**) diagram of a 12 L drying dehumidifier used in the experiment in front of the ventilating pipe. The detailed descriptions and uncertainties of the experimental equipment are shown in Table 2.  
Experimental setup:  
Before the experiment, the gaps were sealed in the door of the experimental cable room with tin foil. The electric heating wire was adjusted to a stable temperature through a voltage regulator; a certain temperature and humidity (28 \({}^{\circ}\)C, 50%) were maintained in \begin{table}
\begin{tabular}{c c c} \hline \hline
**Equipment** & **Parameter** & **Measuring Accuracy** \\ \hline experimental cable room & 420 \(\times\) 280 \(\times\) 830 mm & / \\ electric heating wires & Length: 565 mm & / \\  & Radius: 0.5 mm & / \\  & Evaporation capacity: & \\ humidifier & 200 mL/h, & / \\  & Power: 28 W, & \\ single-phase voltage regulator & Voltage: 220 V & / \\  & Power: 5000 W & / \\  & Power: 230 W & \\  & Dehumidification capacity: & \\
12 L drying dehumidifier & 0.29 kg/h & / \\  & Maximum air volume: & \\  & 100 m\({}^{3}\)/h & \\  & Power: 6 W, & \\ pipeline axial flow fan & Maximum air volume: & / \\  & 36 m\({}^{3}\)/h & \\  & Measuring range: & Temperature Accuracy: \\ K-type thermocouple & \(-\)200 \({}^{\circ}\)C\(\rightarrow\)1372 \({}^{\circ}\)C & \(\pm\)0.2\% + 0.7 \({}^{\circ}\)C \\ anemometer & Use range: 0–0.99 m/s & Velocity accuracy: \(\pm\)0.02 m/s \\ pressure gauge & Use range: 0–10 Pa & Pressure accuracy: \(\pm\)0.1 Pa \\  & Temperature range: & Temperature accuracy: \\  & \(-\)20–60 \({}^{\circ}\)C & \(\pm\)1.5 \({}^{\circ}\)C; \\ hygrothermograph & Humidity range: 0–100\% & Humidity accuracy: \(\pm\)3.0\%; \\  & Dew point temperature range: & Dew point temperature \\  & Dew point temperature & accuracy: \\  & \(-\)50 \({}^{\circ}\)C\(\rightarrow\)60 \({}^{\circ}\)C & \(\pm\)1.5 \({}^{\circ}\)C \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Summary table of experimental equipment. Figure 6: (**a**) Diagram of the internal structure and measurement points of the experimental cable room; (**b**) diagram of the ventilation duct and corresponding measurement points in the improved experimental cable room.