PMMA Application in Piezo Actuation Jet for Dissipating Heat of Electronic Devices

Abstract

The present study utilizes an acrylic (PMMA) plate with circular piezoelectric ceramics (PC) as an actuator to design and investigate five different types of piezo actuation jets (PAJs) with operating conditions. The results show that the heat transfer coefficient of a device of PAJ is 200% greater than that of a traditional rotary fan when PAJ is placed at the proper distance of 10 to 20 mm from the heat source, avoiding the suck back of surrounding fluids. The cooling effect of these five PAJs was calculated by employing the thermal analysis method and the convection thermal resistance of the optimal PAJ can be reduced by about 36%, while the voltage frequency, wind speed, and noise were all positively correlated. When the supplied piezoelectric frequency is 300 Hz, the decibel level of the noise is similar to that of a commercial rotary fan. The piezoelectric sheets had one of two diameters of 31 mm or 41 mm depending on the size of the tested PAJs. The power consumption of a single PAJ was less than 10% of that of a rotary fan. Among the five types of PAJ, the optimal one has the characteristics that the diameter of the piezoelectric sheet is 41 mm, the piezoelectric spacing is 2 mm, and the length of the opening is 4 mm. Furthermore, the optimal operating conditions are a voltage frequency of 300 Hz and a placement distance of 20 mm in the present study.

Investigations on Five PMMA Closed Types of Piezo Actuators as a Cooling Fan

“…Figure 3 displayed the XRD (X-Ray Diffraction) patterns of the circular piezoelectric sheet of Lead Zirconate Titanate (PZT), which revealed the chemical formula of Pb (Zr 0.44 Ti 0.56 )O 3 as same as the Ref. [ 1 ]. The present study utilized the matter of the PMMA with a density of 1.16 g/cm 3 , a melting point of 135 °C, a glass temperature of 102 °C, thermal conductivity of 0.23 W/(mk), and a tensile strength of 78 MPa, which were fabricated by the skill of the insert injection molding process of the vapor chamber (VCRHCS) [ 24 , 25 , 26 , 27 ] as same as the Ref.…”

“…The Ref. [ 1 ] of open PAJ verified the diameter of the piezoelectric sheet of 41 mm, which straightly impacted the performance of the device of the closed type of piezo actuator (Closed PA) as a cooling fan. And the present experiment employed the five PMMA structural design patterns to explore the performance of the closed PA device.…”

“…The present study utilized the matter of the PMMA with a density of 1.16 g/cm 3 , a melting point of 135 °C, a glass temperature of 102 °C, thermal conductivity of 0.23 W/(mk), and a tensile strength of 78 MPa, which were fabricated by the skill of the insert injection molding process of the vapor chamber (VCRHCS) [ 24 , 25 , 26 , 27 ] as same as the Ref. [ 1 ] and the strength can be improved outstandingly and lower the defect of the welding lines.…”

“…Chang et al [ 1 ] utilized a PMMA plate with two circular piezoelectric ceramics (PCs) as an actuation jet named by the open PAJ for dissipating the heat of electronic devices in the previous study. The results showed that the heat convection effect was greater than that of a traditional rotary fan and the power consumption of a single open PAJ was less than 10% of that of a rotary fan.…”

Investigations on Temperatures of the Flat Insert Mold Cavity Using VCRHCS with CFD Simulation

“…They are also used in other industries, including mobile phones, computers, high-precision optical fiber connectors, CD films, and light guide plates. This is due to the improvement in the quality of plastic materials and the development of types [ 9 , 10 , 11 ]. These products have good electrical and mechanical properties and are lightweight and easy to process with corrosion resistance and no-conductivity [ 12 ].…”