## 3 Results
### CFD Study  
In the first phase of the CFD study, initially, the airflow distribution was validated by comparing the experimentally measured air velocities with the CFD-predicted values. Comparisons presented in Tables 4-6 demonstrate a strong agreement between the experimental and numerical results, indicating that the airflow behavior was accurately captured by the simulation model. Upon successful validation of the airflow characteristics, it was concluded that the CFD setup could reliably predict the flow field within the system. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Calculation** & **Point 1** & **Point 2** & **Point 3** & **Point 4** \\ \hline CFD & 5.94 & 6.88 & 8.06 & 7.98 \\ EXP & 6.56 & 7.94 & 7.99 & 8.69 \\ Error & \(-9\%\) & \(-13\%\) & \(1\%\) & \(-8\%\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Velocity [m/s] comparison for Type 1. Figure 11: Type 3 measurement plot. In the second phase of the study, an induction hob was analyzed numerically to make an evaluation for electronic component temperatures. The model contains four electronic components attached to the heatsinks. When creating the result monitoring graphs, the component closest to the fan (IGBT 1) and the component furthest from the fan (IGBT 2) were taken as reference points. To evaluate the numerical analyses, different points were identified at the heatsink outlet, and air velocity measurements were conducted experimentally. These measurements were then compared with the air velocities obtained from the numerical results. Figures 12 and 13 below show a comparison of the surface temperatures of the IGBT 1 and IGBT 2 components for three different types of heatsinks. IGBT 1 is positioned as the closest component to the cooling fan, while IGBT 2 is located as the second closest inverter module relative to the fan, as shown in Figure 1 above. A computational fluid dynamics (CFD) approach was employed using the FloEFD 2021 software package. Within FloEFD, the solution process for steady-state simulations involves iterative solving of the governing equations (continuity, momentum, and energy) until the predefined convergence criteria are satisfied. The term \"iteration\" used in Figures 11 and 12 specifically refers to the solver iterations performed during the steady-state solution process. Each iteration represents an incremental numerical step where the residuals of the governing equations are progressively minimized, leading the solution towards convergence. Therefore, \"iteration number\" corresponds to the number of solver steps needed to achieve convergence, and it does not represent time steps or transient progression. As seen in the results above, the comparison between the experimental and CFD-predicted air velocities for all heatsink types (Tables 4-6) demonstrated a generally good agreement. The calculated Z-scores, based on the total uncertainty of 0.5284 m/s, were predominantly below 2 across all measurement points, indicating that the deviations between experimental and CFD results are within acceptable limits. Therefore, the CFD model was deemed validated in terms of airflow prediction. As illustrated in Figures 12 and 13, the surface temperatures of IGBT 1 and IGBT 2 modules show observable differences depending on the heatsink configurations. It is important to note that, during actual induction hob assembly (as depicted in Figure 1), IGBT modules are thermally bonded to the heatsink using thermal interface materials (TIMs) such as thermal paste to minimize contact resistance and enhance heat transfer efficiency. However, in the simplified CFD model developed for this study, the effect of thermal paste was not explicitly modeled. According to the heatsink supplier, the thermal paste introduces an additional thermal resistance of approximately 0.5 \({}^{\circ}\)C/W. Therefore, when interpreting the CFD results, this additional resistance should be considered as a correction factor, slightly increasing the predicted IGBT surface temperatures in real-world conditions.