Thermal performance of multiple piezoelectric-magnetic fans

Previous studies introduced novel multiple piezoelectric-magnetic fans (“MPMF”) which can improve its thermal performance effectively with only one piezoelectric actuator. Moreover, the T-shaped fan design also can increase sweep area of fan to drive more air and improve its thermal performance. This study focuses on investigating the effect of fan pitch (P) and gap (G) between fan tip and heat sink. In order to analysis the improvement of thermal resistance, efficiency of MPMF system is defined as the improvement of thermal resistance compared with natural convection in this study. The results show that MPMF can reach the optimal efficiency of MPMF system of 73.53% while aspect ratio of fan pitch (P/L) is 0.23 and the ratio of gap between fan tip and heat sink (G/L) is 0.05. In addition, the cooling ability under different dummy heater power is explored. When dummy heater operates at 90W, the surface temperature of heater can be declined from 187.9°C to 77.3°C. Comparing with the thermal performance of rotary fan (0.25°C/W, 1.8W), thermal resistance of MPMF is 0.62°C/W with the power consumption of 0.15W, 6.7% of the rotary fan.