Temperature distribution analysis in parallel plate treatment chamber for pulsed electric field processing: Numerical study

Abstract

Studies on temperature distribution in parallel plate treatment chambers are limited due to its design which is more prone to arcing, thus, neglecting its use in continuous processing. Therefore, this study discusses the temperature distribution due to Joule heating in a parallel plate treatment chamber acting in continuous mode. The numerical results predict that at a slow flow rate (i.e., 0.0234 cm3/s), the fluid flow near the chamber wall is in a static state (0 cm/s), thus, increasing its residence time and resulting in receiving more pulses. In this situation, the temperature increased dramatically from 25 °C (inlet temperature) to approximately 58 °C, i.e., 132 % increment. On the other hand, a slight increase in temperature (i.e., < 27 °C) is predicted by numerical simulation at a higher flow rate (i.e., 0.138 cm3/s) at the same location (near the chamber wall). This less rise is due to the low residence time which causes the liquid to quickly leave the treatment area, thus, getting less pulse. The temperature soar in this condition is very low which is approximately 8 % of the inlet temperature. From the results obtained, flow rate control helps to reduce the temperature rise, thus, keeping the temperature at ambient temperature or slightly above the ambient and at the same time reducing the risk of the treated media from experiencing adverse effects on its physical attributes as a result of high temperatures.