50 hz and 100 hz respectively fig6 shows that the temperature of the component is initially 88 u00b0 c and is reduced by 10 on degrees after applying the acoustic waves for 10 minutes fig7 also shows that the temperature is reduced below 70 u00b0 c after 10 minutes of acoustic wave application after the acoustic wave application was suspended the temperature of the component went back up to the initial value fig8 shows that 100 hz wave has little effect on the cooling of the component fig6 to 8 indicate that there is an optimal frequency for cooling a heat generating component by inducing a resonance of flow fig9 shows the relationship between the frequency of the acoustic waves and rate of temperature change it shows that the maximum reduction of temperature of the heat generating component is 12 percent when the frequency of the acoustic waves is around 50 hz to find out the effect of the amplitude of the driving signal on the temperature change the cooling apparatus was operated with a fixed frequency of 50 hz while varying the amplitude of the signal fed to the acoustic vibrator rate of temperature change is depicted in fig1 which indicates that the maximum reduction of temperature is around 16 volt the effects of the frequency and amplitude of a driving signal on the temperature change is summarized in fig1 which shows the distribution of the rate of temperature change when varying the frequency and amplitude of a driving signal the frequency and amplitude for obtaining maximum temperature change depend upon characteristics of each electronic devices such as size or shape etc the cooling apparatus of the present.