High-power post-positioned gas spring hybrid thermoacoustic electric generator: Dynamic and stable performance characterization

Lightweight and high-performance portable power supplies are essential for meeting electricity demands in specialized application scenarios. Hybrid thermoacoustic electric generators have garnered significant attention in this domain due to their high efficiency and power density. However, as existing research has predominantly focused on low-power prototypes, there remains a lack of comprehensive understanding regarding the dynamic behavior and operational limits of high-power hybrid thermoacoustic electric generators exceeding the 10-kW class. To bridge this gap, this work presents a comprehensive experimental study on a post-positioned gas spring hybrid thermoacoustic electric generators prototype, characterizing its performance under diverse transient and steady-state conditions. The prototype successfully achieved a maximum electrical power output of 15 kW with a thermal-to-electric efficiency of 32.5%. Experimental results reveal that the system's sensitivity to load resistance amplifies significantly at higher heating power levels, a phenomenon elucidated through an analysis of the acoustic impedance matching mechanism. Furthermore, the gas spring and gas bearing systems demonstrated robust adaptability, maintaining stable operation across varying charging pressures and gravitational orientations with performance deviations of less than 8%. By verifying the engineering feasibility of high-power post-positioned gas spring hybrid thermoacoustic electric generators and mapping their critical energy flows, this study provides vital guidelines for the upscaling and optimization of future thermoacoustic power systems.