Session: K13-02: EVAPORATION AND POOL BOILING FROM ENHANCED SURFACES

Paper Number: 138021

138021 - Laser Etching for Enhanced Cooling in Pool Boiling 

Abstract: 

With the miniaturization of electronics, there is a demand for cooling small areas independently or hotspots on a larger baseplate among other electronics. Pool boiling is a common topic of study because it has the potential of high heat flux cooling and heat transfer effectiveness. Thermal resistance for cooling is minimized by removing additional layers interfaces in the device stack.  The integration of enhanced boiling structures directly in electronic substrate material is therefore highly attractive.  Aluminum nitride is a common substrate in electronics packaging with excellent thermal conductivity and electrical insulation properties but is difficult to machine for enhance surface structures.  However, UV laser ablation can be used to quickly pattern different cooling structures directly into aluminum nitride. A method of using a UV laser to etch microscale porous structures, in the form of pin fins, directly into aluminum nitride is presented. These structures show excellent thermal performance in pool boiling, with critical heat flux reaching 240 W/cm² and maximum heat transfer coefficient of 12 W/cm²·K in water.  This talk explores the effect of the pin-fin geometry and placement on heat transfer performance.  In particular, the potential of patterns in porous structure to direct liquid and vapor flow and promote liquid supply into the boiling area is considered.

Presenting Author: Roman Giglio UC Merced

Presenting Author Biography: Roman Giglio is a PhD Candidate at the University of California, Merced. Giglio's research is in two-phase heat transfer.

Authors:

Roman Giglio UC Merced
Muhammad Shattique University of California: Merced
Gokce Ozkazanc Guc University of California, Merced
James Palko University of California: Merced