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Troubleshooting of an electrohydrodynamic (ehd) drying system

Dehydration is very important for food preservation during storage and transportation. Today, food dehydration is done mostly by forced air convection. Forced air convection uses a psychrometrically controlled air flowing over food products to remove water content. This process consumes a lot of energy due to high airflow rates. A method to reduce to reduce energy consumption, called Electrohydrodynamic drying (EHD), uses high voltage electrodes at low current to create a secondary airflow. The high voltage electrode creates an electric field where current is passed through the air to a grounded plate that a food sample sits on. This passing of current through the air creates a secondary airflow due to interaction between the flowing electrons and air molecules. This secondary airflow allows a significant decrease in the primary airflow due to forced convection, therefore decreasing the total power consumption. Research in EHD drying has been conducted in partnership between ONIRIS (a food science engineering higher education institution in Nantes France) and Grove City College since 2013. The research has involved the Grove City College study-center study-abroad program based in Nantes France. The program allows for Mechanical and Electrical engineering students to study abroad for a full semester. In the 2015-2016 academic year, a team of senior electrical engineering students participated in the study abroad program. The students were required to complete a senior design project. The goal of this project was to replicate the EHD drying experimental apparatus used at ONIRIS, but at a significantly reduced cost. The purpose of this study is to present the work done on improving the design of the EHD drying, and the presentation of initial testing results, during a three-semester independent study since the system’s completion at the end of the 2015-2016 academic year.