A numerical approach in predicting flow field induced by randomly moving nano particles

Way Lee Cheng, Reza Sadr

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

There have been several reports that suspending nanoparticles in a fluid, or nanofluids, can enhance heat transfer properties such as conductivity. However, the extend of the reported enhancement is inconsistent in the literature and the exact mechanisms that govern these observations (or phenomena) are not fully understood. Although the interaction between the fluid and suspended particles is suspected to be the main contributor to this phenomenon, literature shows contradicting conclusions in the underlying mechanism responsible for these effects. This highlights the need for development of computational tools in this area. In this study, a computational approach is developed for simulating the induced flow field by randomly moving particles suspended in a quiescent fluid. Brownian displacement is used to describe the random walk of the particles in the fluid. The steady state movement is described with simplified Navier-Stokes equation to solve for the induced fluid flow around the moving particles with constant velocity at small time steps. The unsteady behavior of the induced flow field is approximated using the velocity profiles obtained from FLUENT. Initial results show that random movements of Brownian particles suspended in the fluid induce a random flow disturbance in the flow field. It is observed that the flow statistics converge asymptotically as time-step reduces. Moreover, inclusion of the transitional movement of the particles significantly affects the results.

Original languageEnglish
Title of host publicationASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013
PublisherAmerican Society of Mechanical Engineers (ASME)
DOIs
Publication statusPublished - 2013
EventASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013 - Hong Kong, China
Duration: 11 Dec 201314 Dec 2013

Other

OtherASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013
CountryChina
CityHong Kong
Period11/12/1314/12/13

Fingerprint

Flow fields
Fluids
Navier Stokes equations
Flow of fluids
Statistics
Nanoparticles
Heat transfer

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes

Cite this

Cheng, W. L., & Sadr, R. (2013). A numerical approach in predicting flow field induced by randomly moving nano particles. In ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013 American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/MNHMT2013-22113

A numerical approach in predicting flow field induced by randomly moving nano particles. / Cheng, Way Lee; Sadr, Reza.

ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013. American Society of Mechanical Engineers (ASME), 2013.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Cheng, WL & Sadr, R 2013, A numerical approach in predicting flow field induced by randomly moving nano particles. in ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013. American Society of Mechanical Engineers (ASME), ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013, Hong Kong, China, 11/12/13. https://doi.org/10.1115/MNHMT2013-22113
Cheng WL, Sadr R. A numerical approach in predicting flow field induced by randomly moving nano particles. In ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013. American Society of Mechanical Engineers (ASME). 2013 https://doi.org/10.1115/MNHMT2013-22113
Cheng, Way Lee ; Sadr, Reza. / A numerical approach in predicting flow field induced by randomly moving nano particles. ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer, MNHMT 2013. American Society of Mechanical Engineers (ASME), 2013.
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