کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
786833 1466416 2015 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of concentration on R134a/Al2O3 nanolubricant mixture boiling on a reentrant cavity surface
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی مکانیک
پیش نمایش صفحه اول مقاله
Effect of concentration on R134a/Al2O3 nanolubricant mixture boiling on a reentrant cavity surface
چکیده انگلیسی


• Measured pool boiling of R134a/nanolubricant mixtures on a Turbo-BII-HP surface.
• Nanolubricants improve boiling when nanoparticles concentrated and well dispersed.
• Nanoparticle surface density used to predict refrigerant/nanolubricant boiling.

This paper quantifies the influence of Al2O3 nanoparticles on the pool boiling performance of R134a/polyolester mixtures on a Turbo-BII-HP boiling surface. Nanolubricants with 10 nm diameter Al2O3 nanoparticles of various volume fractions (1.6%, 2.3%, and 5.1%) in the base polyolester lubricant were mixed with R134a at two different mass fractions (0.5% and 1%). The study showed that nanolubricants can improve R134a boiling on a reentrant cavity surface as long as the nanoparticles remain well dispersed in the lubricant and are at sufficiently large concentration. For example, three of the refrigerant/nanolubricant mixtures with the smallest nanoparticle mass fraction exhibited average enhancements over the entire heat flux range of approximately 10%. However, when the nanoparticle mass fraction was increased to a point that likely encouraged agglomeration, an average heat transfer degradation of approximately 14% resulted. An existing model was used to predict the boiling heat transfer.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Refrigeration - Volume 49, January 2015, Pages 36–48
نویسندگان
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