As one of the cleanest energy source, liquefied natural gas(LNG) plays an essential part in the world energy market. This study proposes to utilize the LNG cold exergy and low-temperature waste heat with a three-stage traveling-wave thermoacoustic engine(TWTAE) coupled with linear alternators(LA). Numerical simulation is conducted to optimize the performance of this system. The effect of multiple factors of both the looped thermoacoustic engine(TAE) and the LA has been investigated. The three-stage traveling-wave thermoacoustic electric generator (TWTAG) operating with 4 MPa Helium under a temperature difference of 110-500 K is able to extract 15 kW acoustic power while the output electric power is nearly 13 kW. The overall exergy-to-acoustic efficiency is 44.2% while the heat-to-electric efficiency is nearly 40%.
Keywords : thermoacoustic; power generator; traveling wave; cold exergy; liquefied natural gas