Design and decoupling analysis of Thermal–Electric energy comprehensive utilization scheme based on “diamond” active cooling thermal protection system for hypersonic vehicle

High–temperature aerodynamic heat threatens the safe cruise of hypersonic vehicles, but it also contains huge energy utilization potential. In this study, the thermal–electric energy comprehensive utilization scheme was proposed to combine the energy conversion technology (ECT) with active cooling thermal protection system (ACTPS). The mass flow rate (M) varied from 0.008 kg s−1 to 0.2 kg s−1 for each channel with the inlet fluid temperature being set to 253 K. It was investigated that the leading edge of the "Enhanced" model forms longitudinal swirls. The inner and outer wall temperatures of the "Enhanced" model were lower than 275 K and 650 K, respectively, at mass flow rate of 0.076 kg s−1. Moreover, the thermoelectric performance of five different parameters (Bi2Te3 height (L1), SiGe height (L2), width for unit (H), inner wall temperature (Tin) and heat power (QT)) was explored. L1 = 1.0 mm, L2 = 0.5 mm and H=1.5 mm were selected as the optimal parameters combination for engineering applications. Within the range of QT from 0.15 W to 0.9 W, the variations range of rated current (Irc), energy conversion efficiency (ηe) and specific power (Ps) for the optimal parameters were 140 mA–460 mA, 0.69 %–2.61 % and 0.016 W g−1–0.373 W g−1, respectively.