As modern-day electronics develop, electronic devices become smaller, more powerful, and are expected to operate in more diverse configurations. However, the thermal control systems that help these devices maintain stable operation must advance as well to meet the demands. One such demand is the advent of flexible electronics for wearable technology, medical applications, and biology-inspired mechanisms. This paper presents the design and performance characteristics of flexible electrohydrodynamic (EHD) pumps, based on EHD conduction pumping technology in macro- and mesoscales. Unlike mechanical pumps, EHD conduction pumps have no moving parts, can be easily adjusted to the microscale, and have been shown to generate and control the flow of refrigerants for electronics cooling applications. However, these pumping devices have only been previously tested in rigid configurations unsuitable for use with flexible electronics. In this work, for the first time, the net flow generated by flexible EHD conduction pumps is measured on a flat plane in various configurations. In this study, the results show that the flexible EHD conduction pumps are capable of generating significant flow velocities in all size scales considered in this study, with and without bending. This study also proves the viability of screen printing as a manufacturing method for these pumps. The selection of working fluid for EHD conduction pumping is also a topic of discussion. Novec Engineered Fluids have been a popular choice for EHD pumping; however, long-term testing has shown that some Novec fluids degrade over time.

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This experimental and numerical study investigates Micro-Encapsulated Phase Change Material (MEPCM) heat transfer characteristics and corresponding pressure drop. To conduct this study, an experimental setup consisting of a steel tube with an inner diameter of 4.3mm, outer diameter of 6.5mm and a length of 1,016mm is selected. A MEPCM mass concentration of 20% slurry with particle diameter ranging between 5–15μm is included in this study. Tube wall temperature profile, fluid inlet, outlet temperatures, the pressure drop across the tube are measured and corresponding Nusselt number are determined for various operating conditions. The experimental results are used to validate the numerical model predictions. The numerical model results show good agreement with the experimental data under various operating conditions. The controlling parameters are identified and their effects on the heat transfer characteristics of micro-channels with MEPCM slurries are evaluated.

Drying of moist porous media such as paper, pulp and food products is one of the most energy intensive processes in industry. Impinging jet nozzles are commonly used in various drying processes. There have been many efforts to improve the transport characteristics of impinging jet nozzles. Utilizing innovative Slot Jet Reattachment (SJR) nozzle is an approach to make the drying process more efficient. This is mainly because these nozzles overcome the high flow rate constraint associated with the traditional Slot Jet (SJ) nozzle. In this paper, the drying characteristics of the SJR nozzle with exit angles of +20˚ and +45˚ are experimentally investigated. The samples used are snack cookies. The results are compared with those of SJ nozzle under the same mass flowrate. The results indicate that significant enhancements in drying rates are achievable with both SJR nozzles compared to SJ nozzle.Keywords: Drying; Porous Food Snack; Slot Jet Reattachment Nozzle; Slot Jet Nozzle