Efficient and sustainable electrical power generation is critical to the U.S. energy supply/security and economy, and it is dominated by thermo-electric systems as the 83% of the electricity in 2018 has been generated from fossil fuels and nuclear energy. The efficiency of the electrical power production is bottlenecked by the performance of a steam generator, i.e., flow boiler, which is caused by a local premature water dryout from excessive unwanted vapor blankets. To address this challenge, the proposed research will a multifunctional wick structure is proposed for effective liquid-vapor separation, to simultaneously advance current technical limits on heat transfer coefficient and maximum heat transfer rate per given surface area without creating significant hydraulic pressure drop. A key success of the propose research requires advanced manufacturing approach for the proposed multifunctional wick structure with complex geometries. The PI will conduct the research working with a collaborator at University of Nebraska, Lincoln (UNL) using the-state-of-the-art metallic 3D printer with the high resolution at Nano-Engineering Research Core Facility (NERCF). Also, this fellowship will greatly strengthen the collaboration between the WSU and UNL. The obtained new knowledge will be implemented into the education plans, which empower future engineering workforce.
A flow boiling system is crucial to various energy and thermal management applications. However, as the system demands miniaturization and high power energy consumption, the level of the heat dissipation is expected to exceed the maximum cooling power of the conventional flow boiling system, Critical Heat Flux (CHF). The CHF is caused by the premature dryout at the flow exit, resulting in catastrophic system burnout, which is caused by two-phase flow instability. Despite of extensive research, currently there is no viable solution to mitigate CHF for long flow channel. The objective of the proposed research is to understand tailored two-phase flow instability and phase-change heat transfer mechanisms using the synergistic combination of the developed mechanistic model, 3D printed multifunctional wicks, i.e., shark-fin-like microporous structures, and in-situ/ex-situ experimental validations. The proposed research will focus on three research thrusts: (a) development of mechanistic models, predicting the tailoring CHF and Heat Transfer Coefficient (HTC) mechanisms, (b) development of the additive manufacturing with the controlled micropore sizes/geometries, while working with collaborator at University of Nebraska, Lincoln by using the-state-of-the-art metallic 3D printer with the high resolution, Lumex Avance-25 at Nano-Engineering Research Core Facility (NERCF), and (c) in-situ/ex-situ experimental validations of enhanced CHF and HTC. The research outcomes enable the developments of efficient, scalable, and robust flow boiling systems including power plant, electronic cooling, and aerospace applications
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
