Excavations at the Giro mine located in the commune of Sainte-Marie-aux-Mines (France) have revealed a metallic and cylindrical artifact that resembles a connecting element for wooden duct sections. Early modern literature, and especially De Re Metallica, mention such technologies intended in particular to force the ventilation of otherwise unbreathable underground mines. The connecting element was found in a gallery leading to a stope of which ventilation seems problematic. The numerical simulation of the air flow in the tunnel makes it possible to test the ventilation hypotheses formulated from archaeological data. These simulations are performed with OpenFOAM, a free and open source software for computational fluid dynamics (CFD). Simulating not only the air flow, but also the heat and CO 2 production of five miners at work highlights the need to force venting in the underground with a ventilation system. It also appears that the construction of scaffolding in the stope can fulfill the double function of facilitating circulation and improving ventilation. This first quantitative approach to one of the main obstacles to mining offers a new method for testing the solutions implemented by miners of the past.