Control standing wave ratio in the loop-tube-type thermoacoustic system

In the loop-tube-type thermoacoustic system, the repetitive cycle of traveling wave makes the traveling wave can also store the acoustic energy. Thus, in the loop, the acoustic energy can be deposited with both state of traveling wave and standing wave, which make the acoustic field much complicate and sensitivity in the loop. In this paper, an equivalent acoustic circuit of a loop-tube-type thermoacoustic system is built and analyzed the standing wave ratio using electro-mechano-acoustical analogy. It is found that the resistance, the inertance and compliance of the components in the system can influence strongly on the standing wave ratio. Furthermore, the detail study on the standing wave ratio using the linear thermoacoustic theory is described. The effect on the standing wave of the key parameters will be discussed, and criteria will be given to obtain an optimal standing wave ratio in the system.