SUBJECT: Ph.D. Proposal Presentation
BY: Luis Lorenzini Gutierrez
TIME: Thursday, December 7, 2017, 11:00 a.m.
PLACE: MARC Building, 201
TITLE: Computational Modeling and Experimental Validation of Single Phase and Boiling Flows in Microgap Cooling Layers
COMMITTEE: Dr. Yogendra Joshi, Chair (ME)
Dr. Mostafa Ghiaasiaan (ME)
Dr. Suresh Sitaraman (ME)
Dr. Muhannad Bakir (ECE)
Dr. Satish Kumar (ME)


The microelectronics industry has been driven by the trends of miniaturization and increased functionality; however, the complexities of processing have prompted the research of alternatives as the physical limits of silicon are being reached. The vertical stacking of integrated circuits (3D ICs) offers several advantages over planar electronics. One of the main challenges for enabling such technology is the reduction of the available volume for heat dissipation. Microfluidic interlayer cooling is a feasible solution for the thermal management of such devices, but several challenges remain to achieve a comprehensive solution that is compatible with electrical and structural considerations. In the present work, different thermal demonstration vehicles (TDVs) are numerically and experimentally studied in an effort to provide a practical cooling solution for 3D ICs and conciliate the multidisciplinary challenges of such. A contribution is made in the single and two-phase modeling by proposing an approach that is capable of accurately predicting the fully-resolved temperature and flow fields across the entire cooling layer and capturing non-trivial aspects such as hotspot cooling. The physics of flow boiling in such layers are extensively studied by means of proposing and adapting a mechanistic phase change model that can be used with commercial computational codes. The model was tested and developed starting from flow boiling simulations in a single microchannel and comparing with flow boiling correlations, evolving until the point of simulating cooling layers with variable density of pin fins and hotspots, and validated with in-house experimental data that has also provided useful insights about the flow regimes and their thermal and hydraulic implications.