Ph.D.
A new numerical method is proposed to study two-phase flow and heat
transfer for interlayer cooling of the new generation of multi-stacked
computer chips. The fluid flow equations are developed in 3-dimensions
based on the Arbitrary Lagrangian-Eulerian formulation (ALE) and the
Finite Element Method (FEM), creating a new two-phase method with an
improved model for the liquid-gas interface.
A new adaptive mesh update procedure is also proposed for effective
management of the mesh at the two-phase interface to remove, add and
repair surface elements, since the computational mesh nodes move
according to the flow. The Lagrangian description explicitly defines the
two-phase interface position by a set of interconnected nodes which
ensures a sharp representation of the boundary, including the role of
the surface tension. The new methodology for computing the curvature
leads to accurate results with moderate programming effort and
computational cost. Static and dynamic tests have been carried out to
validate the method and so far all the obtained results have compared
well to analytical solutions and experimental results found in the
literature, demonstrating that the new proposed methodology to simulate
two-phase flows provides good accuracy to describe the interfacial
forces and bubble dynamics. The new code was then used to simulate
elengated bubble flows in square microchannels, being considered for
two-phase interlayer cooling in future 3D-IC compute chips.