Thermal diffusivity measurement of copper nanofluid using pulsed laser thermal lens technique

Abstract

The pulsed laser thermal lens technique was used to study the thermal diffusivity of fluids containing copper nanoparticles (Cu-NPs) prepared by γ-irradiation method. The samples were prepared for the different concentrations of Cu precursor at 20.KGy dose. A Q-switched Nd-YAG pulsed laser of wavelength 532.nm was used as an excitation source and He-Ne laser was used as a probe beam in the present thermal lens experiment. It was found that the thermal diffusivity of the solution depends on the density of Cu-NPs.

Photothermal and Heat-Transfer Properties of Aqueous Detonation Nanodiamonds by Photothermal Microscopy and Transient Spectroscopy

“…After the formation of the united thermal field, the transient curve depends on the thermal diffusivity of the bulk sample. This is confirmed by our previous findings on aqueous fullerene clusters and significant fitting errors of transient curves for metal nanoparticles with eq S7 for the homogeneous media. , This may result in the overestimation of the bulk thermal diffusivity and, thus, incorrectly advantageous properties of the medium as a nanofluid. Thus, only the part of a transient curve from 500 to 1600 ms was used to measure the actual bulk thermal diffusivity of the sample.…”

“…Photothermal spectroscopy ( PTS ) based on noncontact, nondestructive optical detection of thermal relaxation of the radiation absorbed by the object is well suited for the diagnostics of complex systems. − PTS has a high sensitivity for determining small amounts of various substances and is used for both thermal and optical parametersthermal conductivity, thermal diffusivity, heat capacity, refractive index, absorptivity, etc.with sufficient accuracy. − Photothermal-based microscopy or microspectroscopy ( PTM ) is used for label-free imaging of nonfluorescent species at the level of single molecules and shows the highest sensitivity among optical-absorption methods. − PTM modalities provide images of tissues, , cells, , and single and assembled nanoparticles , with confocal modalities ,− and a high resolution challenging the diffraction limit due to the combined use of optical and time-resolved thermal imaging governed by the characteristic rates of nonradiative heat transfer. ,, …”

Approach to the Assessment of Size-Dependent Thermal Properties of Disperse Solutions: Time-Resolved Photothermal Lensing of Aqueous Pristine Fullerenes C60 and C70

“…This fact also contradicts with the data for determination of the thermal diffusivity of gold and TiO 2 nanoparticle-containing samples. 91−93 It is also interesting that fitting of transient curves for metal nanoparticles with eq 8 also did not provide good fitting, which was neglected by the authors, 59,162 which supports our data. From approximately 400 ms from the start of the heating curve (ca.…”

Laser fabrication of Cu nanoparticles based nanofluid with enhanced thermal conductivity: Experimental and molecular dynamics studies

“…The mechanisms underlying the process of solid Cu ablation in ethylene glycol (EG) are shown in figure 1. During the initial stage of the ablation process, the temperature of the target material is raised locally due to the multi-photons absorption process at the surface [16,37]. The irradiation of a metallic target through a liquid layer can drive a number of interrelated phenomena.…”

“…Secondly, this laser-induced plasma will expand adiabatically to create a shock wave, which results in extra pressure and temperature [38,39]. Moreover, energy transformation occurs during the expansion and condensation of the plasma plume, which causes the formation of a thin layer of EG vapor (figure 1.c) [37][38][39]. This formed EG layer of vapor will also expand into a cavitation bubble, while the plasma plume enters a cooling phase and shrinks leading to a decrease in pressure and temperature [38] (figure 1.d).…”