## 4 Cooling System Design and Cooling Simulation Based on UG and Moldflow
### Cooling Process Simulation and Analysis
#### 4.3.3 Analysis and Comparison of Cooling Results  
Based on the establishment of the cooling system model, the selection of injection process parameters and the establishment of the mold gating system mentioned above, the cooling simulation was carried out for the two groups of cooling system design solutions. As evident from Figure 10, the simulation results reveal that the product employing the conventional cooling system attains a maximum temperature of 105.1 degrees Celsius at the end of the cooling process, whereas the product incorporating the conformal cooling channels exhibits a significantly lower maximum temperature of 77.02 degrees Celsius. The cooling system with conformal cooling channels demonstrates higher efficiency in the cooling process compared to the traditional cooling system, leading to a more uniform and lower temperature distribution of the plastic parts. Figure 11 presents the detailed temperature distribution within the part. Based on the findings obtained from the simulation results, it is apparent that the utilization of conformal cooling channels in the product design results in lower temperatures compared to conventional cooling channels, accompanied by a more homogeneous temperature distribution. The implementation of conformal cooling channels in the product design leads to improved heat transfer efficiency from the product surface to the cooling medium. Furthermore, the arrangement of these channels has the potential to enhance the uniformity of temperature distribution on the product surface by mitigating the occurrence of hot spot areas, which are localized regions with elevated temperatures. The strategic placement of cooling channels in proximity to these hot spot areas facilitates effective heat dissipation, resulting in reduced temperature gradients and enhanced uniformity of temperature distribution. \begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline  & **DOE-1** & **DOE-2** & **DOE-3** & **DOE-4** \\ \hline Objective function & Minimizing cooling time & Minimizing cooling time & Minimizing cooling time & Minimizing cooling time \\ \hline \multirow{4}{*}{Design Variables} & Channel diameter (d) & Channel diameter (d) & Channel diameter (d) & Channel diameter (d) & Channel diameter (d) \\ \cline{2-5}  & Radius Circular (r) & \multirow{2}{*}{Top-width (a) Circular (r)} & \multirow{2}{*}{Width (a) Width (b) Height (h) Height (h) Height (h) Height (h) Height (h)} \\ \cline{3-5}  & & & & \\ \hline \multirow{4}{*}{Constraints} & Cooling time \(<35\) s & Cooling time \(<35\) s & Cooling time \(<35\) s & Cooling time \(<35\) s \\ \cline{2-5}  & 4 mm & \multirow{2}{*}{\(<\) d \(<\) 6 mm} & \multirow{2}{*}{\(4\pi<\frac{(a+h)b}{2}<\frac{4\pi}{2}<\frac{(b-a)^{2}}{2}\pi<\frac{4\pi}{2}< \frac{4\pi}{2}<\frac{4\pi}{2}<\frac{4\pi}{2}<\frac{4\pi}{2}<\frac{4\pi}{2}< \frac{4\pi}{2}<\frac{4\pi}{2}\)} \\ \cline{1-1} \cline{3-5}  & & & & \\ \hline \end{tabular}
\end{table} 
Table 4: Optimization problem statements for DOE-1, DOE-2, DOE-3 and DOE-4. Among them, the shapes of the conformal cooling channels are circular, trapezoidal, dome, and rectangular, respectively. Figure 11: Detailed temperature distribution within the part. (**a**) Specific temperature of the part with conventional cooling channels. (**b**) Specific temperature of the part with conformal cooling channels. Figure 10: Simulation results for the temperature of a part after the cooling process (**a**) Temperature of the part with conventional cooling channels. (**b**) Temperature of the part with conformal cooling channels. From Figures 12 and 13, it is evident that the time required to reach the ejection temperature using conventional cooling channels is 34.39 s, whereas the time using conformal cooling channels is reduced to 24.19 s, resulting in a significant reduction in cooling time by 10.20 s. This reduction in cooling time underscores the superior performance of conformal cooling channels over conventional cooling channels in achieving the desired ejection temperature.