The development of thermoacoustic refrigeration technology has been held back by low power density and high required temperatures. The present work proposes and simulates a compact, multi-stage loop thermoacoustic refrigeration system with integrated stages connected by a short thermal buffer tube at the heating-cooling section interface. This arrangement improves power density and reduces friction losses. Designed to operate at a cooling temperature between 200 and 290 K, and powered by low-grade heat input at around 450 to 600 K at 2.0 MPa mean pressure and 293 K ambient temperature, the system can achieve relatively high power density and low onset temperature. Simulation results show a four-stage system can produce a maximum cooling power output of around 5 to 10 kW with an overall axial length of less than 12 m. The system also requires a low onset temperature difference at approximately 35 K between heat input and ambient for the system to sustain limit cycle oscillations.
Keywords thermoacoustic, refrigeration, engine, waste heat, compact