Many soft materials of industrial importance such as pastes, gels, concentrated dispersions and emulsions fail to attain thermodynamic equilibrium over practical time scales due to jamming of constituent entities. Such soft materials, known as soft glassy materials, have very high viscosity and show extremely slow relaxation behavior. In this work heat transport behavior of a model soft glassy material, namely aqueous suspension of laponite is studied. Laponite is synthetic nanoclay with particles of disc-like shape, diameter 25 nm and thickness 1 nm. For concentrations above 1 volume % the aqueous system forms a space filling gel that supports its weight. In the present work, thermal diffusivity of laponite suspension in deionized water is investigated with laser interferometry. A sample is placed in an octagonal cavity comprising fixed copper plates on the top and bottom sides. Initially, the sample is at a uniform temperature. Collimated laser light beam generated from He-Ne laser with 632.8 nm wavelength is passed through the test cell. The interferometer is aligned in the infinite fringe setting, obtained by balancing the refractive index of the laponite suspension against a reference cell filled with glucose solution. At certain time instant (t = 0), the temperature of top surface is increased by 1–3°C. The interference patterns are analyzed to obtain the time dependent temperature field. This data is regressed against the analytical solution of the unsteady heat conduction problem to determine the thermal diffusivity of the solution. Results show a strong dependence of thermal diffusivity on laponite concentration.
Skip Nav Destination
ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels
July 8–12, 2012
Rio Grande, Puerto Rico, USA
Conference Sponsors:
- Fluids Engineering Division
ISBN:
978-0-7918-4476-2
PROCEEDINGS PAPER
Laser Interferometric Determination of Thermal Diffusivity of Transparent Soft Glassy Materials
K. Muralidhar
K. Muralidhar
IIT Kanpur, Kanpur, India
Search for other works by this author on:
S. S. Bhandari
IIT Kanpur, Kanpur, India
Y. M. Joshi
IIT Kanpur, Kanpur, India
K. Muralidhar
IIT Kanpur, Kanpur, India
Paper No:
FEDSM2012-72228, pp. 259-267; 9 pages
Published Online:
July 24, 2013
Citation
Bhandari, SS, Joshi, YM, & Muralidhar, K. "Laser Interferometric Determination of Thermal Diffusivity of Transparent Soft Glassy Materials." Proceedings of the ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. Volume 2: Fora. Rio Grande, Puerto Rico, USA. July 8–12, 2012. pp. 259-267. ASME. https://doi.org/10.1115/FEDSM2012-72228
Download citation file:
10
Views
0
Citations
Related Proceedings Papers
Related Articles
Visualization of Iso-Gradient Lines in Convective and Diffusive Systems Using Gradient-Sensing Interferometry
J. Heat Transfer (August,2002)
Heat Transfer to Suspensions of Microencapsulated Phase Change Material Flowing Through Minichannels
J. Heat Transfer (February,2012)
Related Chapters
Thermal Interface Resistance
Thermal Management of Microelectronic Equipment
Chitosan-Based Drug Delivery Systems
Chitosan and Its Derivatives as Promising Drug Delivery Carriers