## 7 Conclusions  
A methodology for obtaining the pressure loss coefficients per unit length that define a compact model of an EMC screen based on a porous media approach was defined for a case in which the approaching flow is a fan-induced one. In addition, correlations predicting the values of the directional pressure loss coefficients as a function of the geometric and operational parameters were introduced. It is concluded that using this compact model offers thermal designers the following advantages with respect to using a detailed model or the modeling proposed by the various handbooks on pressure loss coefficients.  
One advantage is that there is a very significant reduction in the time needed to create the geometry and the mesh, as it is not necessary to generate the geometries of the pores. Between 4 and 24 h is needed to create a detailed model, while no more than 10 min (less than 4% of the initial time) is required to create the compact model.  
A second advantage is that as a consequence of the decrease in the number of elements that the mesh has, the time needed to converge the simulations is drastically reduced. For a detailed model, depending on the geometry, anywhere between 5 h and several weeks is needed to achieve a good level of convergence, whereas with a compact model, thermal designers have a reliable approximation of the flow pattern in 5 min (less than 1.7% of the initial time).  
Therefore, the compact model presented in this work provides a quick and reliable approximation of the flow pattern that is superior to the approximations obtained by the modeling proposed in various handbooks. This approach permits electronic components to be placed into the 3D domain in such a way that a good prediction of the flow close to each component will be obtained quickly.  
Conceptualization, A.B. and R.A.; methodology, R.A.; software, A.B. and G.S.L.; validation, R.A., A.R. and J.C.R.; formal analysis, R.A., A.R. and J.C.R.; investigation, A.B. and R.A.; resources, R.A.; data curation, A.B.; writing--original draft preparation, A.B.; writing--review and editing, A.B., G.S.L., R.A., A.R. and J.C.R.; visualization, A.B., G.S.L., R.A., A.R. and J.C.R.; supervision, R.A.; project administration, R.A.; funding acquisition, R.A. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Eusko Jaurlaritza-Gobierno Vasco, Spain through Proyecto PI2011-30.  
Not applicable.  
This research was funded by Eusko Jaurlaritza-Gobierno Vasco, Spain through Proyecto PI2011-30. The support of Catedra Fundacion Antonio Aranzabal-Universidad de Navarra is also gratefully acknowledged.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Parameter** & \(D\)**(mm)** & \(D_{h}\)**/\(D\)** & \(S\) & \(a\)**(mm)** & \(\epsilon\)**(\%)** & \(\xi\)**(1/mm)** & \(t\)**(mm)** & \(V\)**(m/s)** \\ \hline
**Real value** & 67 & 0.42 & 0.7 & 16 & 0.75 & 0.26 & 1.4 & 1.68 \\ \hline
**Coded value** & \(-\)0.10 & 0.13 & 0.00 & 0.10 & 1 & \(-\)0.66 & \(-\)0.11 & \(-\)0.09 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Real and coded values for each parameter in the new case.