實驗結果顯示，二氧化矽奈米顆粒結構具有較大的熱通量，其因具有良好的表面親水濕潤性，在一大氣壓及過熱度為20 oC時，SiO2-S結構的最大熱通量為677 kW/cm2，是平板結構的2.4倍。在負壓及過熱度為30 oC時，SiO2-S結構熱通量為2391 kW/cm2是平板結構的4倍。最大熱通量及最小蒸發熱阻依序為SiO2-S、SiO2-L、MCM-41、TEOS及平板結構。因此奈米顆粒沉積層結構具有良好的熱傳性能，但MCM-41顆粒的熱性能較差於SiO2-S及SiO2-L顆粒，是因為顆粒本身較難以沉積於加熱表面上方所導致。
This study investigated the effects of silica nanoparticle structures on boiling heat transfer at evaporator. The experiment reveals the effect of thermal performance and bubble growth by nanoparticle structures. The nanoparticle coated structures were used in heating surface of evaporator, and the particles are mesoporous silica nanoparticle (MSM-41), silica nanoparticle (SiO2-S) and silica mircoparticle (SiO2-L), respectively. Comparison of TEOS sol and plat structures are thermal performance with silica particles. The MCM-41 and SiO2-S coated structures contact angle were less than 10 and droplets expanding very fast.
The experimental method of using level adjustable thermosyphon (LAT) and two phase loop thermosyphon (TPLT) are researched of boiling heat transfer in atmospheric pressure and sub-atmospheric pressure, respectively. The working fluid is DI water. During a cycle of experiment, the primary heat transfer mechanisms of LAT is sequentially from natural convection, nucleate boiling, thin-ﬁlm evaporation and dryout in atmospheric pressure, as LAT and TPLT were experimental investigated in pool boiling.
The experimental results show that silica nanoparticle structures have a higher heat flux, because they have better surface wettability of hydrophilic. In the atmospheric pressure and surface superheat is 20 oC, the SiO2-S structure heat flux is 677 kW/cm2. SiO2-S structure heat flux is 2.4 times of plat structure. In the sub-atmospheric pressure and surface superheat is 30oC, the SiO2-S structure heat flux is 2391 kW/cm2. SiO2-S structure heat flux is four times of plat structure. The maximum heat flux and minimum thermal resistance in turn were SiO2-S, SiO2-L, MCM-41, TEOS and plat structures. Therefore, nanoparticles coated structures has better thermal performance. The thermal performance of MCM-41 is poor than SiO2-S and SiO2-L, because it is difficult to coated on the heating surface.