Date of Award
Master of Science
This study investigated the effects of nanoparticles on the heat transfer performance and pressure drop of water for a range of volume fractions of nanoparticles. The nanoparticles used in this study were aluminum oxide with diameters of 100 nanometers. These particles were dispersed in water at volume fractions ranging from zero to 5%. Comparing fluids at the same Reynolds numbers, it was found that the maximum increase in heat transfer for the nanofluid compared to water occurred at the 4% volume fraction. This particular mixture had an average heat transfer coefficient of 17% greater than the water case. The next best enhancement was seen at the 3% volume fraction, where the average heat transfer coefficient was 12% higher than water. The volume fraction that had the lowest change in heat transfer was the 5% volume fraction, raising the heat transfer coefficient by about 8%. The nanofluid theoretical models predicted the experimental heat transfer coefficients to within 8%. Specifically, theoretical values at the 3% volume fraction over-predicted the experimental results by an average of about 3%, while the 4% volume fraction model under-predicted the results by an average of one percent. The largest deviation occurred at the 5% volume fraction, with the model over-predicting the experimental results by an average of 8%. The pressure drops for the nanofluids compared to water were greater by about 32% to 38%. Specifically, the 3% volume fraction had a pressure drop increase of an average of about 32% greater than water. Next, the 4% nanofluid mixture produced an average pressure drop of about 34.5% greater than water. Lastly, the 5% volume fraction had a pressure drop averaging about 38% larger than water.
Steven David Feltes
Feltes, Steven David, "An in-tube heat transfer comparison for nanofluids and water" (2005). Retrospective Theses and Dissertations. 18771.