There have been numerous investigations of nanodiamond-nanofluid systems with many suggesting that considerable property enhancements, e.g., increased thermal conductivity, might be possible. 245-255, Applied Thermal Engineering, Volume 91, 2015, pp. The purification of UDD powders is important for achieving good stable nanofluids. V.C.1 Complex Coolant Fluid for PEM Fuel Cells - Energy During the preparation of UDD powders, igniter is used in the detonation process which causes metal and carbon impurities and those are aggregates or attached to the outer surface of the ND particles. k5fX.TX#HksQ}
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An investigation has been undertaken into the stone processing machines. [27] model and Mouromtseff number [31] is used to study the heat transfer benefits of PG/W based ND nanofluids in laminar and turbulent flow conditions. 499-508, Energy Conversion and Management, Volume 96, 2015, pp. Table 8-3-1 - Properties of mixture Water/Glycol - CERN Results showed that ND nanofluids achieved higher heat transfer coefficients than the base fluid. The purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. How about a secondary heat exchanger, i.e primary steam/water heats intermediate water. Intemediate water is pumped to a secondary heat exchanger w Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC 27401, USA. To create stable nanofluids, the ND nanoparticles are ultrasonically agitated with EG for 4h. At a constant heat flux of q=9099W/m2, experiments were carried out in a laminar flow with Reynolds numbers ranging from 264.4 to 2194.4. Nanodiamond (ND) nanoparticles of primary particle size of 510nm can be produced in large quantity by using commercially available ultra-dispersed diamond (UDD) powders. For 1.0% vol. 180 30
electrical They also observed the formation of carboxyl groups on the surface of ND particles based on the FTIR analysis. The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. However, experimental studies that jointly explore the physical properties of hybrids and the corresponding mono nanofluids are missing.
The dataset includes 13 different nanofluids with temperature from 30.00 to 149.15C, particle size from 5.00 to 150.00nm, particle thermal conductivity from 1.20 to 1000.00W/mk, particle volume fractions from 0.01 to11.22%, and base fluid thermal conductivity from 0.11 to 0.69W/mk. The thermal performance of the internal heat transfer fluid was an important factor affecting the heat transfer efficiency of the exchanger system. 0000017674 00000 n
The carbon impurities present in the UDD powders have been removed using mixture of H2SO4 and HNO3 [5], [6], [7], [8], [9]. The reason for the agglomeration of UDD powders in the base fluid is due to the presence of carbon impurities. Pressure and temperature variation of the electrical conductivity of The preparation and properties of hybrid nanofluids containing diamond nanoparticles are analyzed and discussed in detail, and a list of potential uses for these enhanced heat transfer fluids in industrial and commercial applications is provided and deliberated. The sensitivity analysis illustrated that temperature has the highest effect on the relative TC followed by base fluid TC and particle volume fraction. Thereby, nanofluids have proven to be useful in applications, especially electronic cooling, where increasing thermal properties and avoiding electrical conductivity are vital. WebDOWFROSTfluid is a formulation of 95.5 percent propylene glycol, dipotassium phosphate and water. 107-98-2) Propylene Glycol Methyl Ether Acetate (PMA; CAS No. WebMaintains low electrical conductivity Uses proprietary non-ionic corrosion inhibitor formulation with years of research Can be used with Formulation: Propylene Glycol, Measuring glycol concentrations by electrical conductivity is not recommended, especially in process systems, heat exchangers, etc. The quality of 8 . This study investigates the potential of composite allotrope boron nitride nanobarbs (BNNBs) as nanoparticles for enhancing the thermal conductivity of nanofluids based on mixtures of ethylene glycol and propylene glycol with water. Future research should focus on enhancing the dispersion stability of BNNB nanofluids and exploring the influence of BNNB morphology on the thermal conductivity and other thermophysical properties of nanofluids. 0000142997 00000 n
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WebIn this work, mono B 4 C and TiB 2 and hybrid TiB 2:B 4 C nanoadditives are used for the first time to design nanofluids based on propylene glycol:water 20:80 wt%. 0000002335 00000 n
Experimental research was done on the heat transfer, entropy generation, and exergy efficiency of ethylene glycol (EG) based nanodiamond (ND) nanofluids flowing in a circular tube. WebPropylene Glycol Methyl Ether (PM; CAS No. 0000003320 00000 n
Copyright 2023 Elsevier B.V. or its licensors or contributors. 0000000918 00000 n
The strong acid treatment on UDD powders, the carboxyl groups are formed on the surface of ND particles, which can be clearly observed in the IR spectra (red line). WebBNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. The Choi [1] and his team developed nanofluids (fluids contain nanometer size particles) and obtained higher thermal conductivity compared to base fluids. In this study, more than 3200 data of thermal conductivity of nanofluids were collected from literature to develop simple-to-use and accurate correlations for predicting relative thermal conductivity of nanofluids. BNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. Energy . At 1.0vol% of nanofluid and a Reynolds number of 1454.4 in comparison to the base fluid, the Nusselt number and heat transfer coefficient are boosted by 29.43%, 45.01%, and a friction factor penalty of 27.59%, respectively. Vajjha and Das [24] also prepared 60:40% (weight ratio) of EG/W based Al2O3, CuO and ZnO nanofluids and measured thermal conductivity up to 10.0vol.%. The B4C mono nanofluid shows the highest improvements of thermal conductivity (6.0%) and electrical conductivity (70 times higher), but also the highest viscosity increases (5154%). A sawing test and a simulation were carried out to analyze the sawing trajectory, the surface topography of the segments and the percentage of worn diamond particles. However, the penalty in friction factor and pressure drop is 17.28% and 14.24% under the same Reynolds number and 1.0vol% nanofluid over the base fluid. Prasher et al. However, those results have not been collectively compared or discussed. Correlations for the thermo-physical properties of the nanofluid were developed. The results showed that the Turbiscan stability index of N-CQDs nanofluid was about 1.5 and the T value fluctuated within 0.5%, showing excellent stability. The hybrid nanofluid presents intermediate values between those of the mono nanofluids for all the properties except dynamic viscosity. Propylene glycol Due to the different particle sizes and shapes of nanoparticles, the proposed model can better predict the thermal conductivity and viscosity of N-CQDs nanofluids compared with other empirical models. Reynolds numbers were in the range 10100 and fluid inlet temperatures ranged from 5 to 40C. Webconductivity. BNNBs are allotrope composites composed of boron nitride nanotube cores with walls decorated with attached hexagonal boron nitride crystals, creating a jagged morphology that facilitates the formation of a connected network and contributes to the enhancement of thermal conductivity in nanofluids. 0000125049 00000 n
The fluid is colorless (water white). [14,15] for mono nanofluids based on the same base fluid, propylene glycol:water 20:80 wt%. [25], [26] also prepared 20:80%, 40:60% and 60:40% EG/W based Fe3O4 nanofluids and measured both thermal conductivity and viscosity experimentally. Joint School of Nanoscience and Nanoengineering, North Carolina A&T State University, Greensboro, NC 27401, USA
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Among all the carbon materials ND particles creates great interest because of their superior hardness, thermal conductivity, i.e. Common uses: antifreeze/heat transfer fluid. of nanofluid, the exergy efficiency is 22.97%, while for ethylene glycol, it is 6.78%. Nanodiamondwater nanofluids were prepared and estimated the thermal conductivity, viscosity and also estimated their potential use in heat transfer applications. conductivity of propylene glycol Under constant heat flux conditions, ZnOPG nanofluids exhibited linear increase in heat removal rates with increasing nanoparticle concentration. The relative electrical conductivity of -SiC NFs and model predictions determined at 298.15 K are compared as illustrated in Fig. Because of the poor electrical conductivity of the -SiC particles compared to the base ethylene glycol and propylene glycols ( p < < bf), case (1) therefore holds accordingly. 0000089466 00000 n
The ultra-sonication technique was employed for preparing the mixture and results showed that the stability and thermal conductivity enhancements of Al2O3H2O nanofluids are highly dependent on sonication time and the energy supplied to the fluid for its preparation. 0000033853 00000 n
In this work, mono B4C and TiB2 and hybrid TiB2:B4C nanoadditives are used for the first time to design nanofluids based on propylene glycol:water 20:80wt%. Results show, at 1.0vol% and the Reynolds number of 2702, the heat transfer coefficient and Nusselt number is increased by 36.05%, and 27.47%, respectively, over the base fluid. These plates are to be used in a proposed compact (thin and light-weight) solar thermal flat plate collector (FPC). The heat transfer applications of prepared ND nanofluids in a fully developed laminar flow (Reynolds number, Re<2300) can be evaluated based on the Prasher et al. WebElectrical Conductivity ( S/cm) 55% Propylene Glycol + 45% DI Water + 0.1% Benzotriazole + 0.05% Nanoparticles (Mix# 2) 55% Propylene Glycol + 45% DI Water + 0.1% Benzotriazole + 0.025% Nanoparticles (Mix# 2) Electrical Conductivity vs. Time for the Coolant Formulations in a 1 L Dynamic Test Loop at 70oC 11 New thermal conductivity and viscosity correlations have been developed based on the experimental data. The study also investigated the dispersion stability of BNNBs in different solvents using Hansen Solubility Parameters, revealing that propylene glycol mixtures demonstrated better long-term stability compared to ethylene glycol mixtures. Naik and Sundar [28] prepared 30:70% PG/W based CuO nanofluid and estimated thermal conductivity and viscosity experimentally. Theoretical approach is used to identify the heat transfer benefits of the prepared propylene glycol/water based ND nanofluids in laminar and turbulent flow conditions using the thermal properties. The acid treated ND particles were characterized by XRD, TEM, FTIR and XPS. This study reports a nanofluid that achieves long-term stability without any additives. FROZKHQ KHDWHGLQWKH+9HOHFWULFILHOG Group method of data handling (GMDH) and gene expression programming (GEP) as two white-box powerful models were used for modeling.
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