나노유체에서 파울링 현상이 유동 비등 열전달에 미치는 영향에 대한 연구

Abstract

Abstract A boiling heat transfer is used in various industry such as power generation systems, heat exchangers, air-conditioningand refrigerations. In the boiling heat transfer system, the critical heat flux (CHF) is the important factor, and it indicatedsafety of the system. It has kept up studies on the CHF enhancement. Recently, it is reported the CHF enhancement, whenworking fluid used the nanofluid with high thermal properties. But it could be occurred nanoflouling phenomenon fromnanoparticle deposition, when nanofluid applied the heat transfer system. And, it is reported that the safety and thermal efficiency of heat transfer system could decrease. Therefore, it is compared and analyzed to the CHF and the boiling heat transfer coefficient on effect of artificial nanofouling (coating) in oxidized multi-wall carbon nanotube nanofluids. As theresult, the CHF of oxidized multi-wall carbon nanofluids and the CHF of artificial nanofouling in the nanofluids increased to maximum 99.2%, 120.88%, respectively. A boiling heat transfer coefficient in nanofluid increased to maximum 24.29%higher than purewater, but artificial nanofouling decreased to maximum -7.96%.