*3.1. Pressure Loss Coefficient*

Different exhaust mass flows and their corresponding pressure drops were measured to obtain accurate predictions. Empirical data (Figure 9) show a clear linear correlation between velocity and pressure drop (being *v* the horizontal axis and −Δ*p μL* the vertical axis) and Darcy's law can be employed. The resulting Darcy's constant is *κ* = 1.695 × 10−<sup>8</sup> m2.

**Figure 9.** Plot for viscous resistance derivation. Linear fit constant: B = 5.9 × 10<sup>7</sup> m<sup>−</sup>2.
