The aim of this proposal is to develop novel mechanistic models for describing the pool boiling phenomena on precisely defined nano-fin structures and to experimentally validate these models. By integrating the research topics in this project with the education plans the PI aims to add to the knowledge base and to develop human capital with expertise in the domain of nanoscale transport phenomena as well as multi-phase flows and heat transfer. The PI will achieve the research goals by developing a new fundamental approach involving sensitivity analysis - i.e. by measuring the local and global response of the boiling process to the spatial perturbations caused by the surface nano-structures. The spatial distribution of the micro/nanoscale local surface temperature transients will be measured using high-speed temperature nano-sensors in a dense spatial array. The global heat flux values will be monitored and the bubble dynamics statistics will be explored including the growth rate, departure diameter and frequency. The high volume of experimental data (surface temperature transients) acquired by the large number (1000+) of high speed nano-sensors will be analyzed using computational visualization tools (animations). Non-Equilibrium Molecular Dynamics (NEMD) will be used to estimate the Kapitza resistance (Rk) of the different nano-fin materials (e.g., organic, inorganic, metallic and ceramic) - in order to design boiling surfaces (nano-fins) with better thermal efficacy.
The fabrication/ testing of nano-sensors, molecular models and pool boiling heat flux correlations expected to be developed from this proposed study are of significance for diverse and futuristic applications, including: thermal management (opto-electronics), oil exploration (deep drilling), therapeutics/ biotechnology (rapid thermo-cycling for genomics/ proteomics - amplification/ diagnostics), energy conversion and energy efficiency (HVAC, solar-thermal, geo-thermal and nuclear thermal-hydraulics). School teachers (RET) and minority students (REU) will be trained for developing hands-on learning modules for subsequent use in the classes to kindle the spirit of discovery in the students at an early age. Class-room feedback from teachers will be used to improve the learning modules in successive years. The experimental set-up (nano-sensors and nano-fins) and the simulation results will be used as demonstration modules in courses taught by the PI and the school teachers.