کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7058612 1458078 2013 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental investigation of CO2 thermosyphon flow and heat transfer in the supercritical region
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Experimental investigation of CO2 thermosyphon flow and heat transfer in the supercritical region
چکیده انگلیسی
Due to the unique properties of near-critical fluid, trans-critical/supercritical CO2 based natural circulation loop (NCL, or thermosyphon) has been proposed in many energy conversion systems, such as solar heater, waste heat recovery, next generation nuclear cooling, etc. This paper presents an experimental investigation of a near-critical CO2 thermosyphon. The closed thermosyphon is specially designed for high pressure experiments, where natural convection is achieved only by heating and cooling of fluid in the loop. The system is operated in wide range of pressures from around 6.0 to 15.0 MPa in the near-critical region. It is found that the NCL flow will change from unstable sub-critical two-phase flow to stable liquid flow, and then become stable supercritical circulation with the increase of system initial pressure. The heat transfer behaviors are analyzed for stable flow conditions mainly for supercritical region. General variations of the fluid temperature, mass flow rate and loop pressure are presented in this paper. In the steady supercritical region, the heat transfer performance of the cooler show very small changes with bulk mean fluid temperature, and at the heater better heat transfer is found for conditions close to the pseudo-critical point. The heat transfer dependency on operation pressure and evolution mechanisms are also discussed in detail in this paper.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 64, September 2013, Pages 202-211
نویسندگان
, , ,