## 3 Results and Discussions
### Heat Dissipation Analysis  
The efficacy of heat dissipation stands as a critical characteristic for the performance of shielding chassis, a factor that cannot be overlooked in the design and evaluation of such systems. In this investigation, the COMSOL Multiphysics 6.1 simulation software plays a pivotal role in analyzing the thermal behavior of shielding chassis composed of three distinct materials. To ensure a controlled and uniform basis for comparison, each chassis was initialized at a surface and ambient temperature of 273 K. A consistent heat source, simulating the operational temperature typically encountered by a PCB board at 323 K, was \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Material** & **Nickel-Plated** & **Carbon Fiber** & **Carbon Fiber** & **Stainless Steels** \\ \hline chassis 1, \(\alpha=0^{\circ}/\text{dB}\) & 37.54 & 30.17 & 31.34 \\ chassis 2, \(\alpha=0^{\circ}/\text{dB}\) & 41.11 & 30.46 & 33.23 \\ chassis 3, \(\alpha=0^{\circ}/\text{dB}\) & 46.13 & 30.44 & 42.59 \\ chassis 1, \(\alpha=90^{\circ}/\text{dB}\) & 47.62 & 34.24 & 39.49 \\ chassis 2, \(\alpha=90^{\circ}/\text{dB}\) & 46.13 & 33.97 & 40.72 \\ chassis 3, \(\alpha=90^{\circ}/\text{dB}\) & 43.23 & 34.24 & 37.46 \\ density/g/cm\({}^{3}\) & 1.9–2.2 & 1.4–2 & 7.7–8 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Chassis time-domain SE and weight analysis. \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Temperature** & **Initial/K** & **In 30 s/K** & **In 60 s/K** & **In 90 s/K** & **In 120 s/K** & **In 180 s/K** \\ \hline Metal & 273 & 273 & 273 & 273 & 273 \\ Nickel-Plated Carbon Fiber & 273 & 273 & 274 & 275 & 276 & 278 \\ Carbon Fiber & 273 & 275 & 277 & 280 & 282 & 285 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Change in minimum temperature of shielding chassis surface. Figure 7: Electric field at the observation point of different structural chassis: (**a**) horizontal polarization; (**b**) vertical polarization. strategically positioned at the lower section of each chassis. This setup aimed to replicate real-world operating conditions closely, facilitating an accurate assessment of the materials' thermal management capabilities. The outcomes of this simulation, specifically the spatial temperature distribution on the surfaces of the three types of shielding chassis after a three-minute exposure to the heat source, are meticulously illustrated in Figure 8. The color-coded temperature map provides an intuitive visual representation, with the numerical values at the top and bottom of the color scale indicating the maximum and minimum surface temperatures observed, respectively. A further detailed analysis of the temporal evolution of the surface temperature, particularly focusing on the minimum temperature fluctuations recorded during the three-minute period, is presented in Table 3.  
A comparison of the thermal performance of the three materials is shown in Figure 8 and Table 3. The metal chassis has the best heat dissipation ability, with its surface temperature initially set at 273 K and remaining constant for 180 s, allowing it to conduct heat to the outside world quickly. In contrast, the carbon fiber chassis shows the least cooling ability. From an initial temperature of 273 K, the temperature increased by about 2 K to 3 K between 60 and 180 s, for a total of 12 K in 180 s, making it slow to transfer heat to the outside world. The nickel-plated carbon fiber chassis, on the other hand, has great potential in terms of thermal performance, showing a small increase of 1 K or just over 1 K every 30 s from the initial reading to 180 s, demonstrating a significant increase in thermal performance over carbon fiber. To summarize, the metal chassis comes a distant second in terms of heat dissipation, indicating the best thermal efficiency. Nickel-plated carbon fiber chassis comes in second, showing commendable thermal management capabilities, while carbon fiber chassis falls behind, showing the worst thermal performance.