Experimental study of influence of resonator length on the performance of standing wave thermoacoustic engine

An experimental study of the effect of the resonator length on the performance of standing wave thermoacoustic (SWTE) engine has been presented. Three different resonators length with an opened end were tested. SWTE consists of several main parts, which are a Hot Heat Exchanger (HHX), a Cold Heat Exchanger (CHX), a resonator pipe, and a stack. CHX and HHX were made of copper with 4 cm length. The stack was 3 cm lamination made of stainless steel wire mesh screens with a mesh number of 10. The resonator pipe was made of stainless steel with an inner diameter of 52.5 mm and we were varied to 630 cm, 1020 cm, and 1410 cm. We used battery charger which has power of 231 W to supply heat power into SWTE. This experiment proved that the SWTE with resonator length 630 cm generated the sound with the smallest onset temperature difference and the shortest time to reach the onset condition, those were 200°C and 1310 s, respectively. It also produced the highest pressure amplitude of 5.272 kPa, the highest acoustic power of 20.6 W, and the highest efficiency of 8.9%.