tailieunhanh - Báo cáo hóa học: " Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer"

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: Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer | Parametthanuwat et al. Nanoscale Research Letters 2011 6 315 http content 6 1 315 o Nanoscale Research Letters a SpringerOpen Journal NANO IDEA Open Access Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer Thanya Parametthanuwat1 Sampan Rittidech1 Adisak Pattiya2 Yulong Ding3 and Sanjeeva Witharana3 Abstract This article reports a recent study on the application of a two-phase closed thermosyphon TPCT in a thermosyphon for economizer TPEC . The TPEC had three sections of equal size the evaporator the adiabatic section and the condenser of 250 mm X 250 mm X 250 mm W X L X H . The TPCT was a steel tube of ID. The filling ratios chosen to study were 30 50 and 80 with respect to the evaporator length. The volumetric flow rates for the coolant in the condenser were 1 and 5 l min. Five working fluids investigated were water water-based silver nanofluid with silver concentration w v and the nanofluid NF mixed with 1 and w v of oleic acid OA . The operating temperatures were 60 70 and 80 C. Experimental data showed that the TPEC gave the highest heat flux of about 25 kW m2 and the highest effectiveness of about at a filling ratio of 50 with the nanofluid containing 1 w v of OA. It was further found that the effectiveness of nanofluid and the OA containing nanofluids were superior in effectiveness over water in all experimental conditions came under this study. Moreover the presence of OA had clearly contributed to raise the effectiveness of the nanofluid. Introduction Two-phase closed thermosyphon TPCT as illustrated in Figure 1 is essentially a gravity-assisted wickless heat pipe which utilizes the heat of evaporation and condensation of the working fluid. Contrary to the conventional heat pipe that uses the capillary force to return the liquid to evaporator the TPCT uses gravity to return the condensate. Since the evaporator of a TPCT is located in the lowest position the .