Static and dynamic thermal behavior of carbon based nanofluids
Date of Award
M.S. in Mechanical Engineering
Department of Mechanical and Aerospace Engineering
Advisor: Khalid Lafdi
Nanofluids are a new class of heat transfer fluids which are engineered by dispersing nanometer-sized solid particles or tubes in conventional heat transfer fluids such as water, ethylene glycol, and engine oil. The first part of this study includes carbon nanotube (CNT)-ethylene glycol (EG) suspension as thermal management fluids. Three types of CNTs with various degrees of crystallinity and surface energy were prepared using heat-treatment temperature. The thermal conductivity of nanofluids tested at varying concentration from 0% to 1.2% using static and dynamic thermal tests. The CNT type and volume concentration were investigated at various shear rates. The thermal resistance of the test suspensions decreased with increasing shear rate. These tests showed that CNT with higher crystallinity and concentration exhibit better thermal performance. However, these CNT tend to break down under high shear. Conversely, CNT with medium crystallinity exhibits the best compromise. The second part of the study includes the formulation of a theoretical model for the effective thermal conductivity of nanofluids. The model is based on a novel point of view regarding the arrangement of nanoparticles in the base fluid. The predictions from the model show a reasonably good agreement with the experimental results.
Nanofluids Thermal conductivity, Nanotubes, Carbon, Heat Transmission, Nanofluid; carbon; nanotube; thermal; CNT
Copyright 2013, author
Al Samarrai, Omar Hashim, "Static and dynamic thermal behavior of carbon based nanofluids" (2013). Graduate Theses and Dissertations. 504.