Effect of Nanoconvection due to Brownian Motion on Thermal Conductivity of Nanofluids

Date

2009-08-22

Author

Azizian, M. Reza
AYBAR, HİKMET ŞELLİ
Okutucu Özyurt, Hanife Tuba

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

178
views

0
downloads

A nanofluid is a new class of heat transfer fluids that contain a base fluid and nanoparticles. The use of additives is a technique applied to enhance the heat transfer performance of base fluids. The thermal conductivity of the ordinary heat transfer fluids is not adequate to meet today's cooling rate requirements. Nanofluids have been shown to increase the thermal conductivity and convective heat transfer performance of the base liquids. One of the possible mechanisms for anomalous increase in the thermal conductivity of nanofluids is the Brownian motions of the nanoparticles inside the base fluids. It is shown in this Study that the heat diffusion assumption that has been used in the macro- and micro- composite systems is not valid in the nanofluid systems. Apart from heat diffusion the nanoconvection diffusion that it is due to the indirect effect of Brownian motion is responsible of enhancement in thermal conductivity Of nanofluid systems.

Subject Keywords

Heat Transfer, Thermal Conductivity, Nanofluids, Nanoconvection, Brownian Motion

URI

https://hdl.handle.net/11511/55322

Collections

Department of Mechanical Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Enhanced thermal conductivity of nanofluids: a state-of-the-art review Özerinç, Sezer; Yazicioglu, Almila Guevenc (2010-02-01) Adding small particles into a fluid in cooling and heating processes is one of the methods to increase the rate of heat transfer by convection between the fluid and the surface. In the past decade, a new class Of fluids called nanofluids, in which particles of size 1-100 nm with high thermal conductivity are Suspended in a conventional heat transfer base fluid, have been developed. It has been shown that nanofluids containing a small amount of metallic or nonmetallic particles, Such as Al2O3, CuO, Cu, SiO2,...
THERMOPHYSICAL PROPERTIES OF TWO-PHASE REFRIGERANT BASED NANOFLUIDS IN A REFRIGERATION CYCLE Tekin, Bilgehan; Yazicioglu, Almila G. (2016-07-14) Nanofluids are a class of fluids with nanoparticles suspended in a base fluid. The aim for using nanofluids is often to improve the thermophysical properties of the base fluid so as to enhance the energy transfer efficiency. As the technology develops; the size of devices and systems needs to get smaller to fulfill the engineering requirements and/or to be leading among competitors. The use of nanofluids in heat transfer applications seems to be a viable solution to current heat transfer problems, albeit wi...
Effect of hydrodynamics on the production of pickering emulsions in unbaffled stirred tanks Demirdoğan, Özge; Ayrancı Tansık, İnci; Department of Chemical Engineering (2019) An emulsion is a fluid system obtained by dispersing one of two immiscible liquids in the other. Since this formation is thermodynamically unstable, it has to be stabilized using an emulsifier. Emulsions in which solid particles are used as emulsifiers are called Pickering emulsions. In this study, the investigation of the effect of different hydrodynamic conditions on the production of Pickering emulsions in unbaffled stirred tanks was aimed. Oil in water Pickering emulsions were produced. Distilled water ...
Convective heat transfer enhancement with nanofluids: The effect of temperature-variable thermal conductivity Özerinç, Sezer; Kakaç, Sadik (2010-07-14) A nanofluid is defined as the suspension of nanoparticles in a base liquid. Studies in the last decade have shown that significant amount of thermal conductivity and heat transfer enhancement can be obtained by using nanofluids. In the first part of this study, classical forced convection heat transfer correlations developed for pure fluids are used to predict the experimental values of heat transfer enhancement of nanofluids. It is seen that the experimental values of heat transfer enhancement exceed the e...
EFFECT OF ALLOYING ELEMENTS AND HEAT TREATMENT ON FATIGUE CRACK GROWTH BEHAVIOR OF FE-NI-BASED SUPERALLOYS Topuz, Seher; Gürbüz, Rıza; Batıgün, Caner; Department of Metallurgical and Materials Engineering (2022-12-02) Fe-Ni-based superalloys are characterized by high strength, toughness, and corrosion resistance materials at room and elevated temperature applications. They are generally used in many parts requiring high toughness and ductility, such as aerospace, industrial gas turbine, and industrial components. The mechanical properties of Fe-Ni-based superalloys depend on three main effects. These alloying elements are added to the structure, working processes, and heat treatment. This study investigates the effect of...

Citation Formats

M. R. Azizian, H. Ş. AYBAR, and H. T. Okutucu Özyurt, “Effect of Nanoconvection due to Brownian Motion on Thermal Conductivity of Nanofluids,” 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/55322.