Enhancing CHF of Pool Boiling Using Micro/Nano Structures
Overview
Yu-Chi Chen 陳郁其 & Ya-Ci Xu 許雅慈
Boiling is widely exploited in power generation; for example, about 40% of the total power generated by heat engines in the US is through the Rankine cycle. With increasing reliance on nuclear and solar-thermal power generation in the near future, enhancing boiling heat transfer becomes crucial. The efficacy of boiling heat transfer is characterized by critical heat flux (CHF) and heat transfer coefficient (HTC).
Boiling is widely exploited in power generation; for example, about 40% of the total power generated by heat engines in the US is through the Rankine cycle. With increasing reliance on nuclear and solar-thermal power generation in the near future, enhancing boiling heat transfer becomes crucial. The efficacy of boiling heat transfer is characterized by critical heat flux (CHF) and heat transfer coefficient (HTC).
Current work
We have demonstrated enhanced CHF and HTC in pool boiling using copper nanowire (CuNW) and silicon nanowire (SiNW) array coated surfaces. Both CHF (~ 200 W/cm^2) and HTC (~ 5 W/cm^2*K) of the nanowire (NW) array coated surfaces are about twice their values on plain Si surfaces (published in Nano Letters, 9, pp. 548-553, 2009). Now we working on expoloring the mechanism causing CHF on such surfaces.