Thermal Fluids with High Specific Heat Capacity through Reversible Diels–Alder Reactions

Quaternary molten salt nitrate have been used very practically as medium for energy storage or heat transfer fluid in terms of energy recovery system. Quaternary molten salt nitrate is a mixture that can transfer heat to generate energy such as electricity. Mixed alkaline molten nitrate salt can act as a heat transfer fluid due to their advantageous in terms of heat recovery system due to high specific heat capacity, low vapour pressure, low cost and wide range of temperature in its application. This studies shows about determining the new composition of quaternary molten nitrate salts from different primary salts that can possibly give a high specific heat capacity with low melting point. The mixture of quaternary molten nitrate salts was then heated inside the box furnace at 150°C for four hours and rose up the temperature to 400°C for eight hours. Through heating process, the quaternary molten nitrate alkaline was completely homogenized. The temperature was then dropped to room temperature before removing the mixture from the furnace. The specific heat capacities of each sample were determined by using Differential Scanning Calorimeter, DSC. From the result of DSC testing, Sample 6 gives the highest point of specific heat capacity and low melting point which is 0.4648 J/g°C and 97.71°C respectively. In the nut shell, Sample 6 was chosen as a good mixture with good thermal properties that has a low melting point which is below 100°C but high specific heat capacity that may be a helpful in the application energy recovery system.

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Thermal Analysis of Phase Change Material Based Heat Transfer Fluid in Solar Thermal Collector

ASME 2020 Heat Transfer Summer Conference ◽

10.1115/ht2020-8942 ◽

2020 ◽

Author(s):

Tyler J. E. O’Neil ◽

Celine S. L. Lim ◽

Sarvenaz Sobhansarbandi

Keyword(s):

Heat Capacity ◽

Phase Change ◽

Specific Heat ◽

Specific Heat Capacity ◽

Phase Change Materials ◽

Solar Thermal ◽

Heat Transfer Fluid ◽

Liquid Form ◽

High Specific Heat ◽

Multi Walled Carbon Nanotubes

Abstract Phase change materials (PCMs) are commonly used as energy storage mediums in solar thermal systems. This paper investigates the mixture of PCM doped with nanoparticles to be used as HTFs directly integrated in a U-pipe ETC to be applied in solar thermal collectors. The selected type of PCM-HTF in this study is erythritol (C4H10O4), with high specific heat capacity in liquid form, as well as its unique sub-cooling behavior. In order to overcome the low thermal conductivity of erythritol and further enhance specific heat capacity, a weight concentration of 1% multi-walled carbon nanotubes (MWCNT) is added. Additionally, to insure even distribution of MWCNT and consistent properties of the HTF, triethanolamine (TEA) is proposed to be incorporated as a dispersant. The samples were each tested in a Thermogravimetric Analyzer (TGA) and Differential Scanning Calorimeter (DSC) to analyze their thermal properties. The results from the DSC tests show 12.4% enhancement of specific heat capacity of the proposed HTF mixture as well as nearly 5° C depression of freezing onset temperature. This study allows for the optimization of the operating temperature range of the collector when integrated with these materials, where direct heat gain can be obtained in the collector.

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A New Idea for Improving Heat Fade Performance of Organic Based Friction Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.359 ◽

2011 ◽

Vol 194-196 ◽

pp. 359-362

Author(s):

Gui Hua Hou ◽

Zhan Hong Wang ◽

Yui Chi Cui

Keyword(s):

Heat Capacity ◽

Friction Coefficient ◽

Specific Heat ◽

Specific Heat Capacity ◽

Friction And Wear ◽

Room Temperature ◽

Friction Materials ◽

The Matrix ◽

High Specific Heat ◽

Reference Samples

A new idea for improving heat fade performance of organic based friction materials was invented; the method is to dope high specific heat material to the matrix for increasing the specific heat capacity of matrix. In this paper, selecting mullite as additive, organic based friction samples doping mullite were prepared by thermoforming methods, the specific heat of samples were analyzed by TG-DSC, and its friction and wear were tested by GB/T 5764-1998 in China. The results show that doping mullite to matrix can dramatically improve the heat fade performance of organic based friction materials, the friction coefficient of samples can keep steady among 0.3-0.4 when the test temperature is from room temperature to 350°C,while the friction coefficient of the reference samples without mullite decline from 0.38 to 0.19.

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Novel high specific heat capacity ternary nitrate/nitrite eutectic salt for solar thermal energy storage

Solar Energy Materials and Solar Cells ◽

10.1016/j.solmat.2021.111075 ◽

2021 ◽

Vol 227 ◽

pp. 111075

Author(s):

Jinli Li ◽

Yue Zhang ◽

Youjing Zhao ◽

Min Wang ◽

Ying Yang

Keyword(s):

Heat Capacity ◽

Energy Storage ◽

Specific Heat ◽

Specific Heat Capacity ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Solar Thermal ◽

Solar Thermal Energy ◽

Eutectic Salt ◽

High Specific Heat

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Experimental Study on the Specific Heat Capacity Measurement of Water-Based Al2O3-Cu Hybrid Nanofluid by using Differential Thermal Analysis Method

Current Nanoscience ◽

10.2174/1573413715666191118105331 ◽

2019 ◽

Vol 15 ◽

Author(s):

Andaç Batur Çolak ◽

Oğuzhan Yıldız ◽

Mustafa Bayrak ◽

Ali Celen ◽

Ahmet Selim Dalkılıç ◽

...

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Thermophysical Properties ◽

Volume Concentration ◽

Pure Water ◽

Heat Capacity Measurement ◽

Experimental Results ◽

Hybrid Nanofluid ◽

Capacity Measurement

Background: Researchers working in the field of nanofluid have done many studies on the thermophysical properties of nanofluids. Among these studies, the number of studies on specific heat are rather limited. In the study of the heat transfer performance of nanofluids, it is necessary to increase the number of specific heat studies, whose subject is one of the important thermophysical properties. Objective: The authors aimed to measure the specific heat values of Al2O3/water, Cu/water nanofluids and Al2O3-Cu/water hybrid nanofluids using the DTA method, and compare the results with those frequently used in the literature. In addition, this study focuses on the effect of temperature and volume concentration on specific heat. Method: The two-step method was used in the preparation of nanofluids. The pure water selected as the base fluid was mixed with the Al2O3 and Cu nanoparticles and Arabic Gum as the surfactant, firstly mixed in the magnetic stirrer for half an hour. It was then homogenized for 6 hours in the ultrasonic homogenizer. Results: After the experiments, the specific heat of nanofluids and hybrid nanofluid were compared and the temperature and volume concentration of specific heat were investigated. Then, the experimental results obtained for all three fluids were compared with the two frequently used correlations in the literature. Conclusion: Specific heat capacity increased with increasing temperature, and decreased with increasing volume concentration for three tested nanofluids. Cu/water has the lowest specific heat capacity among all tested fluids. Experimental specific heat capacity measurement results are compared by using the models developed by Pak and Cho and Xuan and Roetzel. According to experimental results, these correlations can predict experimental results within the range of ±1%.

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Development of the room temperature protocol based on room temperature ionic liquids and surfactant ionic liquids for the synthesis of derivatives of 2-amino-thiazoles and thermo-physical analysis of the synthesized derivatives using TGA-DSC.

Current Physical Chemistry ◽

10.2174/1877946810999200519102040 ◽

2020 ◽

Vol 10 ◽

Cited By ~ 1

Author(s):

Chandrakant Sarode ◽

Sachin Yeole ◽

Ganesh Chaudhari ◽

Govinda Waghulde ◽

Gaurav Gupta

Keyword(s):

Thermal Analysis ◽

Heat Capacity ◽

Ionic Liquids ◽

Specific Heat ◽

Specific Heat Capacity ◽

Room Temperature ◽

Heat Capacity Data ◽

General Strategy ◽

Capacity Data ◽

Derivatives Of

Aims: To develop an efficient protocol, which involves an elegant exploration of the catalytic potential of both the room temperature and surfactant ionic liquids towards the synthesis of biologically important derivatives of 2-aminothiazole. Objective: Specific heat capacity data as a function of temperature for the synthesized 2- aminothiazole derivatives has been advanced by exploring their thermal profiles. Method: The thermal gravimetry analysis and differential scanning calorimetry techniques are used systematically. Results: The present strategy could prove to be a useful general strategy for researchers working in the field of surfactants and surfactant based ionic liquids towards their exploration in organic synthesis. In addition to that, effect of electronic parameters on the melting temperature of the corresponding 2-aminothiazole has been demonstrated with the help of thermal analysis. Specific heat capacity data as a function of temperature for the synthesized 2-aminothiazole derivatives has also been reported. Conclusion: Melting behavior of the synthesized 2-aminothiazole derivatives is to be described on the basis of electronic effects with the help of thermal analysis. Additionally, the specific heat capacity data can be helpful to the chemists, those are engaged in chemical modelling as well as docking studies. Furthermore, the data also helps to determine valuable thermodynamic parameters such as entropy and enthalpy.

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Influence of alkaline modification on selected properties of banana fiber paperbricks

Scientific Reports ◽

10.1038/s41598-021-85106-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Abayomi A. Akinwande ◽

Adeolu A. Adediran ◽

Oluwatosin A. Balogun ◽

Oluwaseyi S. Olusoju ◽

Olanrewaju S. Adesina

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Moisture Absorption ◽

Water Volume ◽

Banana Fiber ◽

Fiber Loading ◽

Banana Fibers ◽

Alkaline Modification

AbstractIn a bid to develop paper bricks as alternative masonry units, unmodified banana fibers (UMBF) and alkaline (1 Molar aqueous sodium hydroxide) modified banana fibers (AMBF), fine sand, and ordinary Portland cement were blended with waste paper pulp. The fibers were introduced in varying proportions of 0, 0.5, 1.0 1.5, 2.0, and 2.5 wt% (by weight of the pulp) and curing was done for 28 and 56 days. Properties such as water and moisture absorption, compressive, flexural, and splitting tensile strengths, thermal conductivity, and specific heat capacity were appraised. The outcome of the examinations carried out revealed that water absorption rose with fiber loading while AMBF reinforced samples absorbed lesser water volume than UMBF reinforced samples; a feat occasioned by alkaline treatment of banana fiber. Moisture absorption increased with paper bricks doped with UMBF, while in the case of AMBF-paper bricks, property value was noted to depreciate with increment in AMBF proportion. Fiber loading resulted in improvement of compressive, flexural, and splitting tensile strengths and it was noted that AMBF reinforced samples performed better. The result of the thermal test showed that incorporation of UMBF led to depreciation in thermal conductivity while AMBF infusion in the bricks initiated increment in value. Opposite behaviour was observed for specific heat capacity as UMBF enhanced heat capacity while AMBF led to depreciation. Experimental trend analysis carried out indicates that curing length and alkaline modification of fiber were effective in maximizing the properties of paperbricks for masonry construction.

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A novel model for predicting the effective specific heat capacity of molten salt doped with nanomaterial for solar energy application

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2021.117129 ◽

2021 ◽

pp. 117129

Author(s):

Fan Yuan ◽

Ming-Jia Li ◽

Ya-Ling He ◽

Wen-Quan Tao

Keyword(s):

Heat Capacity ◽

Solar Energy ◽

Specific Heat ◽

Molten Salt ◽

Specific Heat Capacity ◽

Solar Energy Application ◽

Effective Specific Heat ◽

Energy Application ◽

Novel Model

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Effects of SiO2 Nanoparticle Dispersion on The Heat Storage Property of the Solar Salt for Solar Power Applications

Energies ◽

10.3390/en14030703 ◽

2021 ◽

Vol 14 (3) ◽

pp. 703

Author(s):

Zhao Li ◽

Liu Cui ◽

Baorang Li ◽

Xiaoze Du

Keyword(s):

Heat Capacity ◽

Specific Heat ◽

Specific Heat Capacity ◽

Heat Storage ◽

Md Simulations ◽

Interfacial Thermal Resistance ◽

Solar Salt ◽

Salt Ions ◽

Base Salt ◽

Storage Property

The effects of SiO2 nanoparticles on the heat storage properties of Solar Salt (NaNO3-KNO3) are studied using experimental and molecular dynamics (MD) simulations. The experiment results show the specific heat capacity of the molten salt-based nanofluids is higher than that of the pure base salt. We focus on the inference regarding the possible mechanisms behind the enhancement of the specific heat capacity which are considered more acceptable by the majority of researchers, the energy and force in the system are analyzed by MD simulations. The results demonstrate that the higher specific heat capacity of the nanoparticle is not the reason leading to the heat storage enhancement. Additionally, the analysis of potential energy and system configuration shows that the other possible mechanisms (i.e., interfacial thermal resistance theory and compressed layer theory) are only superficial. The forces between the nanoparticle atoms and base salt ions construct the constraint of the base salt ions, further forms the interfacial thermal resistance, and the compressed layer around the nanoparticle. This constraint has a more stable state and requires more energy to deform it, leading to the improvement of the heat storage property of nanofluids. Our findings uncover the mechanisms of specific heat capacity enhancement and guide the preparation of molten salt-based nanofluids.

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