TY - JFULL AU - Kriengkrai Assawamartbunlue and Channarong Wantha PY - 2015/6/ TI - Experimental Investigation on the Optimal Operating Frequency of a Thermoacoustic Refrigerator T2 - International Journal of Mechanical and Mechatronics Engineering SP - 783 EP - 787 VL - 9 SN - 1307-6892 UR - https://publications.waset.org/pdf/10001267 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 101, 2015 N2 - This paper presents effects of the mean operating pressure on the optimal operating frequency based on temperature differences across stack ends in a thermoacoustic refrigerator. In addition to the length of the resonance tube, components of the thermoacoustic refrigerator have an influence on the operating frequency due to their acoustic properties, i.e., absorptivity, reflectivity and transmissivity. The interference of waves incurs and distorts the original frequency generated by the driver so that the optimal operating frequency differs from the designs. These acoustic properties are not parameters in the designs and be very complicated to infer their responses. A prototype thermoacoustic refrigerator is constructed and used to investigate its optimal operating frequency compared to the design at various operating pressures. Helium and air are used as working fluids during the experiments. The results indicate that the optimal operating frequency of the prototype thermoacoustic refrigerator using helium is at 6 bar and 490Hz or approximately 20% away from the design frequency. The optimal operating frequency at other mean pressures differs from the design in an unpredictable manner, however, the optimal operating frequency and pressure can be identified by testing. ER -