tailieunhanh - Báo cáo hóa học: " Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment | Ramesh and Prabhu Nanoscale Research Letters 2011 6 334 http content 6 1 334 o Nanoscale Research Letters a SpringerOpen Journal NANO REVIEW Open Access Review of thermo-physical properties wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment Gopalan Ramesh and Narayan Kotekar Prabhu Abstract The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article thermo-physical properties wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment. Introduction Quench hardening is a commonly used heat treatment process in manufacturing industry to increase the service reliability of components where the material is heated to the solutionizing temperature held for a particular period of time and then quenched into the quenching medium. Quenching during heat treatment involves simultaneous occurrence of different physical events such as heat transfer phase transformation and stress strain evolution and heat transfer is the driving physical event as it triggers other processes 1 . The two phase boiling heat transfer is the predominant mode of heat .