Abstract
Miniaturized thermoacoustic systems are examined in this study for application to electronic equipment. Our previous studies revealed that stable oscillation can be achieved in miniature step-shape thermoacoustic closed-tube systems. However, closed-tube systems present problems: the temperature ratio of the stack cannot be formed to raise the temperature in the system. Moreover, the stack is thin. Miniature thermoacoustic systems have high loss because of the high frequency necessary to shorten the total length. Despite these problems, miniature step-shape thermoacoustic systems can achieve oscillation conditions. This paper concerns a step-shape thermoacoustic system, focusing on the temperature ratio and the quality value as parameters to estimate the loss in a system. Consequently, results show that the efficiency of the thermoacoustic system is improved by adopting a step-shape in the system, with the step-shape system being driven at low temperature.