scholarly journals Wettability Control for Correct Thermophysical Properties Determination of Molten Salts and Their Nanofluids

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3765 ◽  
Author(s):  
Yaroslav Grosu ◽  
Luis González-Fernández ◽  
Udayashankar Nithiyanantham ◽  
Abdessamad Faik
Keyword(s):  
Thermophysical Properties ◽  
Molten Salts ◽  
Laser Flash ◽  
Concentrated Solar Power ◽  
Scanning Calorimetry ◽  
Sample Container ◽  
Low Surface Energy ◽  
Scale Roughness ◽  
Nanoscale Roughness

Proper recording of thermophysical properties for molten salts (MSs) and molten salts based nanofluids (MSBNs) is of paramount importance for the thermal energy storage (TES) technology at concentrated solar power (CSP) plants. However, it is recognized by scientific and industrial communities to be non-trivial, because of molten salts creeping (scaling) inside a measuring crucible or a sample container. Here two strategies are proposed to solve the creeping problem of MSs and MSBNs for the benefit of such techniques as differential scanning calorimetry (DSC) and laser flash apparatus (LFA). The first strategy is the use of crucibles with rough inner surface. It was found that only nanoscale roughness solves the creeping problem, while micron-scale roughness does not affect the wetting phenomena considerably. The second strategy is the use of crucible made of or coated with a low-surface energy material. Both strategies resulted in contact angle of molten salt higher than 90° and as a result, repeatable measurements in correspondence to the literature data. The proposed methods can be used for other characterization techniques where the creeping of molten salts brings the uncertainty or/and unrepeatability of the measurements.

scholarly journals Thermophysical properties of NP2 brand nickel

2021 ◽  
Vol 2119 (1) ◽  
pp. 012135
Author(s):  
D A Samoshkin ◽  
A Sh Agazhanov ◽  
S V Stankus
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Diffusivity ◽  
Thermophysical Properties ◽  
Magnetic Phase ◽  
Laser Flash ◽  
Scanning Calorimetry ◽  
Reference Table ◽  
Laser Flash Technique ◽  
Flash Technique

Abstract The heat capacity and the thermal diffusivity of NP2 brand nickel were investigated in the temperature interval 296–1000…1375 K of the solid-state, including the region of the magnetic phase transformation. Measurements were carried out on samples from one initial ingot by laser flash technique and method of differential scanning calorimetry using LFA-427 and DSC 404 F1 setups, respectively. The thermal conductivity was calculated based on the measured thermophysical properties. The estimated errors of the obtained results were 2–4%, 3–5%, and 2–3% for thermal diffusivity, thermal conductivity, and heat capacity, respectively. For investigated thermophysical properties the fitting equations and the reference table have been received.

Thermal Decomposition Modeling and Thermophysical Property Measurement of a Highly Crosslinked Polymer Composite

2009 ◽  
Author(s):  
Aaron L. Brundage ◽  
Kenneth L. Erickson ◽  
Kevin J. Dowding
Keyword(s):  
Thermophysical Properties ◽  
Thermal Response ◽  
Laser Flash ◽  
Polymer Composition ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Inert Filler ◽  
Temperature Range ◽  
One Step ◽  
Practical Geometry

Thermophysical properties including density, specific heat, and thermal diffusivity of a poly (diallyl phthalate) inert filler composite material were characterized over a wide temperature range from room temperature to 800 °C. Over this temperature range, the material decomposition was approximated by a one-step process with first-order kinetics. Thermal kinetics data were obtained by thermal gravimetric analysis with Fourier transform infrared spectroscopy (TGA-FTIR) and thermophysical properties were obtained from differential scanning calorimetry (DSC) and laser flash diffusivity experiments. The response of the material to radiant heating was simulated with a computational heat transfer, multidimensional, finite element code. Additionally, the experimental uncertainty in the measurements was quantified to estimate the uncertainty in the reaction parameters due to heating rate and variability in inert filler-polymer composition in large sample sizes. Hence, the thermal response and the uncertainty were quantified for a complex decomposing material in a practical geometry for technologically important applications.

scholarly journals Determination of thermophysical properties of prototypes of tin-lithium alloy by differential scanning calorimetry

2022 ◽  
Vol 2155 (1) ◽  
pp. 012016
Author(s):  
V Bochkov ◽  
Yu Ponkratov ◽  
N Nikitenkov ◽  
Yu Baklanova ◽  
Yu Gordienko ◽  
...  
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Thermophysical Properties ◽  
Heat Of Fusion ◽  
Scanning Calorimetry ◽  
Fusion Enthalpy ◽  
Lithium Alloy ◽  
Pristine Sample ◽  
Experimental Complex

Abstract This paper presents a description of research works to determine the thermophysical properties of a tin-lithium alloy with a different percentage of lithium and tin atoms in the alloy. The method of differential scanning calorimetry (DSC) was used for the studies, by which the thermophysical properties of the alloy (temperature of phase transition and enthalpy) were determined. The work was carried out at the TiGrA experimental complex. Studies to determine the enthalpy and temperature of phase transition of prototypes of tin-lithium alloy were carried out in the temperature range from 150°C to 500°C at a heating rate of 10°C/min. The experiments were carried out with a pristine sample of tin (reference) and prototypes of a tin-lithium alloy, the percentage of lithium in which was 20, 25 and 27 at. %. As a result of the work performed, the melting point of the prototypes was determined, which was 224°C and 218°C. The values of the specific heat of fusion (enthalpy) of the investigated alloys were determined, which amounted to 76.5 J/g, 80.7 J/g and 86.3 J/g, respectively.

scholarly journals Effect of Microstructure on Thermophysical Properties of Heat-Treated Duplex Steel

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6043
Author(s):  
Piotr Koniorczyk ◽  
Judyta Sienkiewicz ◽  
Janusz Zmywaczyk ◽  
Andrzej Dębski ◽  
Mateusz Zieliński ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Thermophysical Properties ◽  
Room Temperature ◽  
Laser Flash ◽  
Micro Hardness ◽  
Scanning Calorimetry ◽  
Air Atmosphere ◽  
Steel Bar ◽  
Heat Treated ◽  
Duplex Steel

The purpose of this study is to investigate the effect of heat treatments and resulting changes in microstructure on the thermophysical properties of commercial 1.4462 duplex stainless steel. Three types of heat treatment and a raw sample were used. In the first heat treatment, a duplex steel bar was annealed in an air atmosphere furnace for one hour at 1200 °C and then quickly cooled in water (1200 °C + water). The second heat treatment was the same as the first, but afterwards, the bar was annealed in an air atmosphere furnace for 4 h at 800 °C and then slowly cooled down in the furnace to room temperature (1200 °C + water + 800 °C). In the third heat treatment, the duplex steel bar was annealed in the furnace in an air atmosphere for one hour at 900 °C and then slowly cooled in the furnace to room temperature (900 °C). As a result, the weight percentages of ferrite and austenite in the samples achieved the following ratios: 75:25, 65:35 and 44:56. Light microscope examinations (LM), scanning electron microscopy (SEM), Vickers micro-hardness measurements and thermophysical studies using a laser flash apparatus (LFA), differential scanning calorimetry (DSC) and push-rod dilatometry (DIL) were performed to reveal the microstructure and changes in thermophysical properties including thermal diffusivity, thermal conductivity, thermal expansion and specific heat. Along with presenting these data, the paper, in brief, presents the applied investigation procedures.

scholarly journals A Calorimetric Method for Determination of Heat Capacity of Ceramics for Concentrated Solar Thermal Systems / Skenējošās Kalorimetrijas Metode Siltumietilpības Noteikšanai Saules Kolektoru Keramikā

2013 ◽  
Vol 50 (5) ◽  
pp. 68-73 ◽  
Author(s):  
J. Kalnačs ◽  
V. Grehovs ◽  
G. Mežinskis ◽  
L. Bidermanis
Keyword(s):  
Heat Capacity ◽  
Protective Coatings ◽  
Thermal Contact ◽  
Ceramic Materials ◽  
Concentrated Solar Power ◽  
Scanning Calorimetry ◽  
Thermal Systems ◽  
Continuous Scanning ◽  
Resistant Ceramic

Abstract Differential scanning calorimetry was carried out to determine the heat capacity (Cp) of the high temperature resistant ceramic materials to be used as protective coatings for stainless steel tubes of parabolic trough solar collectors in concentrated solar power (CSP) systems. The Ср(Т) measurements and calculations were performed at continuous scanning in the temperature range 20-800 °С. In the work, calibration curves have been derived for conversion of measuring units from mcV into mW. To achieve a better repeatability of measurements, methods for stabilization of the thermal contact between the sample-containing vessel and the probe have been developed. The Ср(Т) dependence was obtained for different ceramic materials.

Nanoparticles as molten salts thermophysical properties enhancer for concentrated solar power: A critical review

2021 ◽  
Vol 44 ◽  
pp. 103280
Author(s):  
Hatem Ahmad Aljaerani ◽  
M. Samykano ◽  
R. Saidur ◽  
A.K. Pandey ◽  
K. Kadirgama
Keyword(s):  
Thermophysical Properties ◽  
Critical Review ◽  
Molten Salts ◽  
Solar Power ◽  
Concentrated Solar Power
Sign in / Sign up

Export Citation Format

Share Document