Soutenance de thèse de Monsieur Mohammad ONEISSI
14h30 | ISTIA | AMPHI E | 62, avenue Notre-Dame du Lac | 49000 ANGERS
Le 23 janvier 2017
Sujet : Analysis of the flow structure and heat transfer enhancement in a rectangular channel with longitudinal vortices
Directeur de thèse : Monsieur Thierry LEMENAND
The objective of this PhD thesis is to investigate and design a new vortex generator (VG) for enhancing heat transfer in parallel plate-fin heat exchangers. Detailed overview about heat transfer enhancement techniques was presented in a literature review, which are divided into three categories: passive, active and compound techniques. Passive techniques are more commonly used in heat exchangers since they are characterized by their efficiency, economy, ease of manufacturing and lower maintenance efforts. Vortex generators are one of the passive techniques that create secondary flows, disrupt the growth of the boundary layer and create swirling flows that enhance exchange between the walls and the core fluid, thus improving heat transfer.
Finally, based on the analysis of the thermal enhancement mechanisms, a novel configuration for longitudinal vortex generators in common flow up was identified. It relies on decreasing the pressure drop across the channel mainly caused by the vortex generators while maintaining high intensity of multiscaled vortices that enhance the heat transfer and mixing performances.