Abstract
In this report we focus on the total length and the shape of the thermoacoustic cooling system called a loop-tube. It is confirmed that the fundamental resonance mode is desirable for high cooling effect. In addition, vertically long shape is better under the condition of the fundamental resonance mode. The cooling effect was evaluated by temperature decrease at the cooling point. Moreover the relation between the cooling effect and resonance mode was surveyed. From measurement result, loop-tubes resonated the fundamental resonance mode have higher cooling effect than others. Resonance mode relates to the viscous boundary layer formed in channels of stack. It is important that the viscous boundary layer in the case of the fundamental resonance mode keeps thinner than the channel radius of stack. And vertically long loop-tubes have high cooling effect. Under the condition of the same total length, vertically long shape is desirable for high cooling effect.