A Tetralattice™ Gradient Fin: Its Creation and Testing

Rapid Prototyping (RP) has allowed prototypes with complex geometries to be possible during the past decade, such as complex geometry heat exchangers and fins. These structures are modeled after the covalent bonding between the carbon atoms of a diamond. The tetrahedron diamond lattice, or Tetralattice™, is a repeating lattice unit that lends itself to RP. Currently, fabrication of a thermal conduction module using two materials in a gradient fashion from one end to the other using intertwined Tetralattice™ pattern is being attempted at Milwaukee School of Engineering. The stainless steel (SS) portion of the gradient fin was fabricated by employing selective laser melting. The testing of this gradient fin for its performance with the base heated at a constant temperature was targeted and compared with the traditional cylindrical SS fin. Convective heat transfer was found to be enhanced due to the large surface area of the Tetralattice™ structure. A thermal imaging study was also conducted on this gradient fin. Infrared thermography captured data that would be nearly impossible to gather using thermocouples. These tests provided detailed heat transfer characteristics of this Tetralattice™ fin. This project tested the limits on fabrication of a complex geometry gradient fin; the authors project tremendous potential for use of such fins in automotive and aerospace applications.