1. Influence of the dipole moment on the increase in the thermal conductivity of thin films functionalized with azo dyeAmeneh Mikaeeli, Dorota Korte, Tomasz Rerek, Dariusz Chomicki, Bayram Gündüz, Beata Derkowska-Zielińska, Andreas D. Wieck, Oksana Krupka, Michal Pawlak, 2024, original scientific article Keywords: thermal conductivity, thin films, azo dye functionalization, thermal conductivityv Published in RUNG: 23.09.2024; Views: 385; Downloads: 2 Full text (4,40 MB) This document has many files! More... |
2. Measuring thermal diffusivity of azoheteroarene thin layers by photothermal beam deflection and photothermal lens methodsAmeneh Mikaeeli, Dorota Korte, Humberto Cabrera, Dariusz Chomicki, Dariusz Dziczek, Oksana Kharchenko, Peng Song, Junyan Liu, Andreas D. Wieck, Michal Pawlak, 2023, original scientific article Keywords: thin films, photothermal spectroscopy, thermal transport, thermal wave, thermal conductivity, thermal diffusivity Published in RUNG: 21.09.2023; Views: 2018; Downloads: 6 Full text (882,88 KB) This document has many files! More... |
3. Generalized Theory of Thermal Conductivity for Different Media: Solids to NanofluidsMohanachandran Nair Sindhu Swapna, Sankararaman S, 2019, original scientific article Abstract: The advent of nanotechnology in the 21st
century opened a new branch of nanoscience known as
nanofluids, finding a wide range of industrial applications
especially in heat transfer. Though the theory of thermal
conductivity of solids is well established, there is no such
conclusive model to explain the thermal conductivity of
nanofluids. In the present work we propose a generalized
theory for thermal conductivity applicable to materials ranging
from heterogeneous solids, porous materials, nanofluids, and
ferrofluids. The model could explain the effective thermal
conductivity of not only the combination of solids but also
solid−fluid mixtures. The proposed theory could successfully
link the existing models for porous solid materials and
nanofluids as its special cases. The proposed model is verified against experimental data by simulating the theoretical equations Keywords: thermal conductivity, generalised model, Sankar-Loeb model Published in RUNG: 05.07.2022; Views: 1847; Downloads: 0 This document has many files! More... |
4. Absolute Porosity Analysis in Carbon Allotropic Nanofluids: A Sankar–Swapna Model ApproachMohanachandran Nair Sindhu Swapna, SREEJYOTHI S, Sankararaman S, 2020, original scientific article Abstract: Porous materials have gained significant attention in recent years as a class of material exhibiting
interesting chemical and physical properties. The existing methods of porosity analysis have limitations that
prevent absolute porosity measurement. Hence, a technique independent of surface physical properties alone
can give the absolute porosity of the material. The porosity greatly influences the thermal diffusivity of a
material. The manuscript is the first report of employing the Sankar–Swapna model for analyzing the porosity variations in carbon allotropic nanofluids. The model helps not only in getting information about the absolute porosity variations among samples, but also suggests morphological modifications through the thermal diffusivity study using the sensitive single-beam thermal lens technique. The variations in thermal diffusivity and absolute porosity values are also correlated to morphological modifications based on the theoretical model and thereby proposing this as a surrogate method for absolute porosity analysis. Keywords: absolute porosity, Sankar–Swapna model, thermal diffusivity, thermal lens, thermal conductivity Published in RUNG: 04.07.2022; Views: 2048; Downloads: 0 This document has many files! More... |
5. Investigations of the Thermal Parameters of Hybrid Sol–Gel Coatings Using Nondestructive Photothermal TechniquesŁukasz Chrobak, Dorota Korte, Hanna Budasheva, Miroslaw Malinski, Peter Rodič, Ingrid Milošev, Sylwia Janta-Lipińska, 2022, original scientific article Keywords: hybrid sol–gel coatings, non-destructive testing, photothermal radiometry, photothermal beam deflection spectrometry, thermal diffusivity, thermal conductivity Published in RUNG: 03.06.2022; Views: 2545; Downloads: 33 Full text (1,36 MB) |
6. Through-plane and in-plane thermal diffusivity determination of graphene nanoplatelets by photothermal beam deflection spectrometryHumberto Cabrera, Dorota Korte, Hanna Budasheva, Behnaz Abbasgholi N. Asbaghi, Stefano Bellucci, 2021, original scientific article Abstract: In this work, in-plane and through-plane thermal diffusivities and conductivities of a freestanding
sheet of graphene nanoplatelets are determined using photothermal beam deflection spectrometry.
Two experimental methods were employed in order to observe the effect of load pressures
on the thermal diffusivity and conductivity of the materials. The in-plane thermal diffusivity was
determined by the use of a slope method supported by a new theoretical model, whereas the
through-plane thermal diffusivity was determined by a frequency scan method in which the obtained
data were processed with a specifically developed least-squares data processing algorithm.
On the basis of the determined values, the in-plane and through-plane thermal conductivities and
their dependences on the values of thermal diffusivity were found. The results show a significant
difference in the character of thermal parameter dependence between the two methods. In the case
of the in-plane configuration of the experimental setup, the thermal conductivity decreases with the
increase in thermal diffusivity, whereas with the through-plane variant, the thermal conductivity
increases with an increase in thermal diffusivity for the whole range of the loading pressure used.
This behavior is due to the dependence of heat propagation on changes introduced in the graphene
nano-platelets structure by compression. Keywords: graphene nanoplatelets, thermal diffusivity, thermal conductivity, photothermal spectrometry Published in RUNG: 30.11.2021; Views: 2729; Downloads: 71 Link to full text This document has many files! More... |