Alternative Calorimetry Based on the Photothermoelectric (PTE) Effect: Application to Magnetic Nanofluids
Abstract
Photothermoelectric (PTE) calorimetry was applied for the first time for thermal characterization of liquids. Both back and front detection configurations, together with the thermal-wave resonator cavity (TWRC) scanning procedure, have been used in order to measure the thermal diffusivity and thermal effusivity of a particular magnetic nanofluid: carrier liquid—transformer oil, surfactant—oleic acid, nanoparticles' type—{Fe}3{O}4.The investigations were performed as a function of the nanoparticles' concentration. Small increases of thermal diffusivity (from 9.06× 10^{-8} {m}2{\cdot } {s}^{-1} up to 9.84× 10^{-8} {m}2{\cdot } {s}^{-1}) and thermal effusivity (from 450 {W}{\cdot } {s}^{1/2}{\cdot } {m}^{-2}{\cdot } {K}^{-1} up to 520 {W}{\cdot } {s}^{1/2}{\cdot } {m}^{-2}{\cdot } {K}^{-1}) with increasing concentration of {Fe}3{O}4 nanoparticles (from 0 up to 0.623 mg {Fe}3{O}4/{ml} fluid) were observed. The comparison with the photopyroelectric (PPE) method shows that PTE and PPE give similar results but, for the moment, PPE is more accurate.
- Publication:
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International Journal of Thermophysics
- Pub Date:
- September 2015
- DOI:
- 10.1007/s10765-015-1855-x
- Bibcode:
- 2015IJT....36.2441D
- Keywords:
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- Magnetic nanofluids;
- PPE calorimetry;
- PTE calorimetry;
- Thermal parameters;
- TWRC method