Infrared imaging as a means of visually characterizing the thermoacoustic onset process influenced by a Helmholtz resonator

Abstract

Helmholtz resonator can be used as a transmission part to connect the thermoacosutic engine (TE) with its load. However, the resonator may significantly influence the performance of the TE. In order to investigate the impact of Helmholtz resonator on the onset process of a TE, infrared (IR) imaging is firstly used as a visualization method to characterize the onset mechanism. Influence of dimensions of Helmholtz resonator on onset process is analyzed experimentally and theoretically. Results show that Helmholtz resonator reduces the pressure amplitude at onset moment and increases the onset temperature of the TE, which both depend on the acoustic power absorbed from the TE. Onset without sudden increase of pressure amplitude is observed with Helmholtz resonator at resonance length. The paper shows that IR imaging is an effective way to characterize the temperature distribution in TE study.

Multi-physics coupling in thermoacoustic devices: A review

“…Then, a two-sensor method [311][312][313] can be used to calculate the acoustic power along the duct. The velocity field in thermoacoustic devices can be measured by HWA (hot wire anemometry) [314], LDA (laser doppler anemometry) [315] and PIV (particle image velocimetry) [316] while the temperature field can be measured by thermocouples, PLIF (planar laserinduced fluorescence) [316] and infrared imaging [317].…”

Improved Predictions of Onset Temperature In Twin Thermoacoustic Heat Engine by Neural Network Based Calibrated Thermoacoustic Model

“…Furthermore, recently, Wang et al [11] had visualized the onset mechanism characteristics in traveling wave thermoacoustic heat engines using infrared imaging. It was noticed that Gedeon streaming has a significant effect on the axial temperature distribution of the onset and damping processes.…”