Inverse Problem Approach Applied to the Study of Heat Transfer Maximization: shape Optimization of Butterfly Inserts

In the present work it is presented and tested a promising and innovative procedure, based on inverse problem approach, for the heat transfer performance maximization of pipes fitted with butterfly-shaped inserts. They promote heat transfer enhancement by transferring the fluid from pipe wall and mixing it with bulk fluid from the central flow, maximizing mass and heat transports. However, this kind of inserts might be dangerous in some cases due to the existence of important differences in the fluid temperature and heat flux distributions. It is here proposed the implementation of an inverse method to infrared measurements: it allows to assess the local convective heat flux for forced convection flow in pipes with inserts and, thanks to these results, optimize insert geometry to maximize the heat transfer processes. Three different geometries of butterfly inserts were investigated in terms of local and global thermal behavior to obtain, given a specific application, the most effective one. Although the main objective of the present work is the application of an original approach, the experimental outcomes achieved in this study are already suitable for the design of heat transfer apparatuses for processes where product temperature should be precisely monitored (e.g., food and drug sector).