The thermal management of next-generation hybrid electric regional aircrafts poses critical challenges due to extreme heat loads, which could reach more than 2 MW and must be dissipated. This rejected heat can be used in a passive system such as Thermoelectric Generators (TEGs), which can directly convert thermal energy into electrical energy. This work is carried out in the framework of the EU Clean Aviation-funded project TheMa4HERA and it numerically explores the possibility of integrating thermoelectric (TE) technology in the next generation of regional aircrafts. Two case studies are considered: energy recovery from the outflow valve originally used to control the pressure of the cabin and the integration of TEG modules in skin heat exchangers used to partially dissipate heat coming from the fuel cells and/or from the power electronics. The results will permit us to understand the feasibility of implementing TEG technology into these specific conditions in terms of overall power generation. The findings indicate that while TEG integration in the outflow valve offers limited power density, the skin heat exchanger shows significantly higher potential for effective energy recovery.

This Letter reports the feasibility of a structure specifically designed for the control of flexural waves propagating in thin perforated plates. The structure, here denominated as a redirector device, consists of a square array of free holes that splits the impinging beam and transmits sideways their vibrational energy. This behavior is known as a Poisson-like effect, and it was theoretically described in different acoustic structures. This effect is experimentally demonstrated for flexural waves excited in an aluminum perforated plate, and it is explained in terms of a physical mechanism different to that reported for acoustic waves interacting with thin hollow cylinders embedded in water. In addition, a collimator device based also in free holes is designed and validated with the purpose of providing the beam impinging the redirector device. The measurements indicate that the amount of redirected energy is strongly enhanced when a barrier of two-beam resonators is added at the rear side of the redirector. All the designs are validated by an experimental setup employing 1 mm thick aluminum plates.