On the direct design of future open cells foams for thermal science application

• Open cell porous media are designed from scratch using a computational geometry algorithm; • The fluid flow behavior of engineered porous media is similar to the traditional ones. • The numerical approach to simulate the porous media is then validated on the printed foam • A novel method to design and optimize porous media is proposed and validated. Porous media have been demonstrated to be efficient heat transfer surfaces but they must be optimized for any given applications. In this regard, numerical simulations can improve the analyses of heat transfer and fluid flow in porous media, making their design and optimization faster, cheaper, and more reliable. Unfortunately, implementing detailed numerical simulations of stochastic foams is challenging because the geometry of a commercially available foam is usually randomly generated and must be reconstructed with cumbersome and expensive methods, like X-ray tomography. Vice versa, the use of a perfectly known geometry can be very helpful for improving the reliability, consistency and robustness of the numerical analyses. This work demonstrates that it is possible to design from scratch a stochastic open-cell foam using computational geometry algorithms and fabricate it by additive manufacturing. In fact, in the present study, a foam was designed and 3D printed, before being tested and numerically analyzed. When tested, the designed foam performed exactly the same as compared to traditional foam but being the geometry completely known, it was possible to run a direct simulation, opening, for the first time, the opportunity to optimize the thermo-fluid behavior of the porous media. After model validation, foams with the same porosity but different pore density were then numerically simulated, monitoring the corresponding pressure drops. Eventually, observations on interstitial heat transfer coefficients and pumping power were discussed, providing further design insights.