At 1.0vol%, the thermal conductivity enhancements of 12.7% and 22.8%, at 1.0vol%, the viscosity enhancements of 1.57-times and 1.8-times were observed at temperatures of 293K and 333K compared to water data. The fluid is colorless (water white). The starting product, MICRONAL 5428 X, which contains about 43% microencapsulated paraffin with a transformation temperature of 28 The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. Prediction of electrical conductivity of TiO 2 water and ethylene glycol-based nanofluids for cooling application in low temperature PEM fuel cells. 1123-1135, Experimental thermal conductivity and viscosity of nanodiamond-based propylene glycol and water mixtures, https://doi.org/10.1016/j.diamond.2016.07.007, nm can be produced in large quantity by using commercially available ultra-dispersed diamond (UDD) powders. The NTU of SCHE is improved only by 2% over that of the base fluid at the flow rate of 6 lit/min because of the limited improvement of the overall heat transfer coefficient. 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, Portuguese Science and Technology Foundation, Investigations of thermal conductivity and viscosity of nanofluids, Viscosity of alumina nanoparticles dispersed in car engine coolant, Thermal conductivity of ethylene glycol and water mixture based Fe, Experimental determination of thermal conductivity of three nanofluids and development of new correlations, Numerical study of turbulent flow and heat transfer characteristics of nanofluids considering variable properties, Experimental investigation on the thermal transport properties of ethylene glycol based nanofluids containing low volume concentration diamond nanoparticles, Thermal transport properties of diamond-based nanofluids and nanocomposites, Volume fraction and temperature variations of the effective thermal conductivity of nanodiamond fluids in deionized water, Enhanced thermal properties of nanodiamond nanofluids, Increase of nanodiamond crystal size by selective oxidation, Experimental investigation of heat transfer and effectiveness of employing water and ethylene glycol mixture based Fe3O4 nanofluid in a shell and helical coil heat exchanger, Heat transfer and exergy efficiency analysis of 60% water and 40% ethylene glycol mixture diamond nanofluids flow through a shell and helical coil heat exchanger, Laminar convective heat transfer, entropy generation, and exergy efficiency studies on ethylene glycol based nanofluid containing nanodiamond nanoparticles, Experimental and modeling studies of N-doped carbon quantum dot nanofluids for heat transfer systems, Modeling thermal conductivity of nanofluids using advanced correlative approaches: Group method of data handling and gene expression programming, Thermophysical, rheological and electrical properties of mono and hybrid TiB2/B4C nanofluids based on a propylene glycol:water mixture, A new frame saw machine by diamond segmented blade for cutting granite, The significance of scaling effects in a solar absorber plate with micro-channels, Improved transient heat transfer performance of ZnOpropylene glycol nanofluids for energy management, Thermal conductivity and viscosity of water based nanodiamond (ND) nanofluids: An experimental study, Effect of temperature and sonication time on nanofluid thermal conductivity measurements by nano-flash method, Thermo-physical properties of diamond nanofluids: A review. Joint School of Nanoscience and Nanoengineering, North Carolina A&T State University, Greensboro, NC 27401, USA
Diamond circular saws and diamond wire saws present some technological limits, and the marble frame saw cannot process granite by now. 0000003207 00000 n
Based on the results, the thermal conductivity enhancements are 18.8%, 16.8% and 14.1% at 1.0vol.% of 20:80%, 40:60% and 60:40% PG/W based nanofluids. One of the authors (L.S.S.) The thermal entropy generation is decreased by 31.78% and the frictional entropy generation is raised by 22.50% over the basic fluid data at 1.0% and Reynolds number of 1454.4. 1000W/mK and Young's modulus, high electrical resistivity, attractive optical characteristics, and excellent chemical stability and biocompatibility. 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. The main advantages of this measurement technique are short measurement times, easy sample preparation and high accuracy. The values of Ck and C for all the volume concentrations and, The purchased UDD powders were successfully treated using strong acids, dry powders of salt and sucrose to remove carbon impurities. The proportion of micro-fractured and good diamonds in the new frame saw machine are 45% and 25%, respectively, and the productivity of the new machine is between 6 and 15m2/h. 499-508, Energy Conversion and Management, Volume 96, 2015, pp. The findings suggest that BNNBs have great potential for use as thermally conductive nanoparticles in nanofluids for various heat transfer applications. New friction factor and Nusselt number equations were created. [12] also used acid mixtures of perchloric acid, nitric acid and hydrochloric acid (based on the procedure of Jang and Xu [13]) for the removal of carbon impurities from the UDD powders and prepared stable ND nanofluids in the base fluid of 55:45% ethylene glycol/water mixture and observed thermal conductivity enhancement of 18% at 2.0vol.%. The effect of BNNB concentration in carrier fluids on nanofluid thermal conductivity was investigated by introducing BNNBs into ethylene glycol-water and propylene glycol-water mixtures at 010 wt%. 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). [14] also used strong acids of H2SO4 and HNO3 in the molar ratio of 3:1 for the purification of UDD powders and prepared 20:80%, 40:60% and 60:40% ethylene glycol/water mixture based ND nanofluids and estimated both thermal conductivity and viscosity experimentally. 245-255, Applied Thermal Engineering, Volume 91, 2015, pp. xref
please go to the Copyright Clearance Center request page. The purchased ultradispersed diamond (UDD) nanoparticles were treated with strong acid solution to make it into almost single nano-diamond (ND) particles. Ghazvini et al. 5. Thus, the new prototype machine is suitable for sawing granite. 0000087536 00000 n
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The carbon based materials such as multi walled carbon nanotubes (MWCNT), single walled carbon nanotubes (SWCNT), graphene and nanodiamond (ND) materials contain high thermal conductivity compared to other materials. 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. The hot fluid volume flow rate was fixed to 1 lit/min, whereas, the cold fluid (nanofluid) volume flow rate was varied from 2 to 6 lit/min. There have been numerous investigations of nanodiamond-nanofluid systems with many suggesting that considerable property enhancements, e.g., increased thermal conductivity, might be possible. Tyler et al.
. 2016 Elsevier B.V. All rights reserved. It was observed that the position of the thermocouples can result in an under-estimation of the Nusselt number. Copyright Clearance Center request page. startxref
Appl. Accurate estimation of thermal conductivity (TC) of nanofluids is essential in thermophysical studies of nanofluids. 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%). Another method for removing the carbon impurities from the UDD powders is with dry salt or dry sucrose [10]. The as-obtained LAGP thin film also possessed a high ionic conductivity of 2 10 5 S cm 1 at 25 C and a low electronic conductivity value of 1.1 10 9 S cm 1. 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. The exergy efficiency of the SCHE can be increased by 21% using 1.0vol% of nanofluid, but the improvement becomes modest as the volume concentration is increased further. The relative electrical conductivity of -SiC NFs and model predictions determined at 298.15 K are compared as illustrated in Fig. 0000133274 00000 n
In addition, it was found that the proposed models could capture the physically expected trends with variation of temperature, size of nanoparticles, and volume fraction. [27] analysis.knfkbf=1+Cknfbf=1+Cwhere, is the volume concentration, Ck and C are the thermal conductivity and viscosity enhancement coefficients. The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of PG/W mixture based Al2O3, CuO, and Fe3O4 nanofluids. [30] also prepared 20:80%, 40:60% PG/W based Fe3O4 nanofluids and estimated thermal conductivity and viscosity experimentally. For 1.0% and a Reynolds number of 1454.4, the thermal performance factor is increased by 1.194-times above the basic fluid. The PG/W nanofluids are prepared with acid treated ND particles. Group method of data handling (GMDH) and gene expression programming (GEP) as two white-box powerful models were used for modeling. Check with Union Carbide or Dow as they manufacture glycols. I understand they do have a web site. 8 . The two-step approach was used to create ND nanofluids with volume concentrations ranging from 0.2% to 1.0%. It has been shown that water is the best solar energy absorbance among four fluids including water, ethylene glycol, propylene glycol, Zeta potential is a measure of the electric potential difference between the surface of a particle and the surrounding fluid. [15] observed thermal conductivity enhancement of 12% at 0.9vol.% of nanodiamond (ND)-poly (glycidol) polymer brush/EG nanofluids, similarly observed thermal conductivity enhancement of 11% at 1.0vol.% of ND.oleic acid/mineral oil nanofluids. Prasher et al. The frictional exergy destruction is found to contribute together with heat transfer exergy destruction to the total entropy of the SCHE system. Kole and Dey [29] prepared 50:50% PG/W based Al2O3 nanofluids and observed nanofluids obey Newtonian behaviour in the measured temperature range from 10C to 50C. of nanofluid, the exergy efficiency is 22.97%, while for ethylene glycol, it is 6.78%. The purification of UDD powders is important for achieving good stable nanofluids. The formation of carboxyl (COOH) groups on the surface of nanodiamond was analyzed by FTIR. Common uses: antifreeze/heat transfer fluid. The different weight ratios of propylene glycol/water mixtures are used as base. Chemical treatment was used to make ND nanoparticles with an average size of 5.42nm. Corresponding authors, a
If you are an author contributing to an RSC publication, you do not need to request permission
Substance and % by volume in mixture: Minimal working temperature [o C] WebPropylene Glycol Methyl Ether (PM; CAS No. If you are the author of this article, you do not need to request permission to reproduce figures
Absolute deviations lower than 1.5% were obtained between the experimental and predicted data using the aforementioned nanopowder thermal conductivities, as can be observed in Fig. Increasing the concentration of the nanofluid beyond 1.0vol% shows a little improvement in the effectiveness of the heat exchanger. This study investigates theoretically and experimentally the electrical and thermal conductivities of 50/50 water-ethylene glycol based TiO 2 nanofluids with nanoparticle concentrations in the range of 0.05-0.5 vol%. 0000086285 00000 n
The present work focused on the preparation of different weight ratio of PG/W (20:80%, 40:60% and 60:40%) mixture based ND nanofluids and the estimation of thermal conductivity and viscosity experimentally at different particle concentrations and temperatures. If you want to reproduce the whole article
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The reason for the agglomeration of UDD powders in the base fluid is due to the presence of carbon impurities. [19] obtained viscosity enhancement of 80% for midel oil based ND nanofluids at 3.0wt.%. Web9.9 Liquid Water Interfacial Tension: Not pertinent 9.10 Vapor (Gas) Specific Gravity: Not pertinent 9.11 Ratio of Specific Heats of Vapor (Gas): 1.073 9.12 Latent Heat of Vaporization: 306 Btu/lb = 170 cal/g = 7.12 X 105J/kg 9.13 Heat of Combustion: 10,310 Btu/lb = 5,728 cal/g = 239.8 X 105J/kg 9.14 Heat of Decomposition: Not pertinent Similarly, at 1.0vol% and Reynolds number of 2702, the thermal entropy generation is dropped by 38.12%, frictional entropy generation is raised by 12.86%, exergy efficiency is enhanced by 36.48% and thermal performance factor is augmented by 1.2094 times over the base fluid. It is hygroscopic, meaning that it readily absorbs water from the surrounding environment. 0000102258 00000 n
The stable ND nanofluids were prepared by considering 60:40% water+ethylene glycol (weight percentage) mixture as base fluid and the experiments were performed at particle loadings ranging from 0.2% to 1.0% and the Reynolds number ranging from 900 to 4800, respectively. In addition, both cutting efficiency and slab flatness were recorded. Hybrid nanofluids aim to further improve the characteristics of mono nanofluids. However, those results have not been collectively compared or discussed. A. O. Maselugbo, B. L. Sadiku and J. R. Alston,
New thermal conductivity and viscosity correlations were proposed by including the effects of volume concentrations and temperatures. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity. Comparisons with data from literature confirmed the validity and the suitability of the nanoflash technique applied to thermal conductivity evaluation. Energy . Namburu et al. WebIn this study the electrical conductivity of aluminum oxide (Al2O3), silicon dioxide (SiO2) and zinc oxide (ZnO) nanoparticles dispersed in propylene glycol and water mixture After cycling at 25 and 80 C, LiGe alloy was formed at the Li/LAGP interface as investigated by synchrotron high energy X-ray Diffraction (HEXRD) spectra (Figure 3b ). [23] first time prepared 60:40% (weight ratio) of EG/W based CuO nanofluids and observed viscosity enhancement of 4.5-times and 3.1-times at 6.12vol.% at temperatures of 35C to 50C. 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%. A detailed procedure is presented for the implementation and evaluation, by Nano-Flash Method, of thermal conductivity of nanofluids with water as base fluid and at different volume concentrations of Al2O3. The UDD powders contains large quantity of carbon impurities, which can be removed using strong acid treatment, dry salt and dry sucrose to make UDD powders into single ND particles. WebThere are two main types of water glycol mixtures used in heating/cooling systems that mix well in water at any concentration. Further to cme's statement, the injection pump for the feed can be alarmed to allow the user know that there may be a system leak. See the follo WebMaintains low electrical conductivity Uses proprietary non-ionic corrosion inhibitor formulation with years of research Can be used with Formulation: Propylene Glycol, The Choi [1] and his team developed nanofluids (fluids contain nanometer size particles) and obtained higher thermal conductivity compared to base fluids. The other chemicals such as sulfuric acid (H2SO4), nitric acid (HNO3), sodium chloride (NaCl), sucrose (C12H22O11) and propylene glycol (C3H8O2) were purchased from Sigma-Aldrich Chemicals, USA. The X-ray powder diffraction (XRD), transmission, C, respectively compared to their respective base fluids. Scaling effects such as viscous dissipation and entrance effects had insignificant impact on the measured average Nusselt number. The Raman, XRD and TEM analysis are also used on UDD and ND-acid treated nanoparticles.
This study recommends that the volume concentration of Fe3O4/60:40%W+EG nanofluid should not exceed volume concentration of 1.0% because the added benefit of working with concentrations higher than 1.0vol% may not outweigh the added cost and complexities of the nanofluid. The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. The thermal conductivity of single phase heat transfer fluids may be enhanced by dispersing small quantity of solid particles. [14,15] for mono nanofluids based on the same base fluid, propylene glycol:water 20:80 wt%. The heat transfer capability of these single phase heat transfer fluids is limited because of its poor thermal conductivity. 40-48, Applied Thermal Engineering, Volume 90, 2015, pp. Nanoscale, 2023, Advance Article
11 is presented the percentage thermal conductivity enhancement [(knfkbf)/kbf100] for these ratios along with the data with the data of Palabiyik et al. These plates are to be used in a proposed compact (thin and light-weight) solar thermal flat plate collector (FPC). WebUsing the results for propylene glycol/water with corrosion inhibitor and nanoparticles, for over 3,000 hours of operation, the conductivity of the solution would have gone up to about 27 mS/cm-hr. We are continuing our optimization to bring this level down by an order of magnitude (which is accepted by almost all the fuel cell manufacturers). 0000003320 00000 n
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In the heat exchanger, the hot fluid passes through the shell side and the cold fluid (nanofluid) passes through the helical coil side. Measuring glycol concentrations by electrical conductivity is not recommended, especially in process systems, heat exchangers, etc. The quality of Based on the above methods the acid treatment method is more effective compared to other salt and sucrose methods. Nanodiamond (ND) nanoparticles of primary particle size of 510nm can be produced in large quantity by using commercially available ultra-dispersed diamond (UDD) powders. [16] prepared 20% of water and 50% of engine oil based ND nanofluids and obtained thermal conductivity enhancement of 25% at 1.0wt.% Taha-Tijerina et al. *
The theoretical models of Maxwell and Einstein have failed to estimate the thermal conductivity and viscosity of nanofluids as a function of temperature. From the IR spectra, the UDD powders contain some functional groups of H, OH, COOH were clearly observed but the intensity is very low (black line). The specific heat capacity decreases with increasing nanofluid loading. [25], [26] also prepared 20:80%, 40:60% and 60:40% EG/W based Fe3O4 nanofluids and measured both thermal conductivity and viscosity experimentally. Nanodiamondwater nanofluids were prepared and estimated the thermal conductivity, viscosity and also estimated their potential use in heat transfer applications. An enhancement of 4.24% in heat transfer rate was observed with 2vol.% ZnOPG nanofluid. 0
Xu X, Choi SUS. The results showed that BNNBs enhanced thermal conductivity of carrier fluids up to 45%, and the enhancement was proportional to the concentration of BNNBs in the carrier fluid. 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. 0000088462 00000 n
and diagrams provided correct acknowledgement is given. The stability, thermophysical properties and rheological characteristics of N-CQDs nanofluids were investigated. The density, isobaric heat capacity, and thermal conductivity of the nanofluids are determined by the oscillating U-tube, differential scanning calorimetry, and transient hot wire methods, respectively. A binary mixture of propylene glycol and water at 20:80 mass ratio offers protection against freezing up to 265.98 K [13], making it suitable as a heat transfer fluid The inadequacy of the widely used VogelTammannFulcher or WilliamsLandelFerry equations to describe the temperature variation of the vacuum New thermal conductivity and viscosity correlations have been developed based on the experimental data. WebThermal conductivities for some common liquids at temperature 300 K (26.8 oC, 80.3 oF): 1 W/(m K) = 1 W/(m oC) = 0.85984 kcal/(h m oC) = 0.5779 Btu/(ft h oF) = 0.048 Btu/(in h The carbon impurities present in the UDD powders have been removed using mixture of H2SO4 and HNO3 [5], [6], [7], [8], [9]. Branson et al.
Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC 27401, USA. Therefore, there is no literature on the thermal properties of PG/W mixture based ND nanofluids. k5fX.TX#HksQ}
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The stable PG/W mixture based ND nanofluids were prepared by dispersing ND acid treated, The nanodiamond (ND) particles were produced using commercially available ultra-dispersed diamond (UDD) powders. I always eqip the system with a 2" hose connection with check valve so the contractor can use a pump to fill the system those glycol feeders Islam, R.; Shabani, B. The Wilson plot method is used to analyze the helical coil side heat transfer coefficients. provided correct acknowledgement is given. Naik and Sundar [28] prepared 30:70% PG/W based CuO nanofluid and estimated thermal conductivity and viscosity experimentally. Webconductivity. <50C [21]. The purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. Yu et al. This paper investigates the significance of some micro scaling effects in micro-channel absorber plates. Sundar et al. However, conjugate heat transfer and measurement uncertainties were significant. 0000073219 00000 n
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. Sundar et al. 2 shows the IR spectra of UDD powders, acid treated, salt and sucrose milled samples. 0000060250 00000 n
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.
34590-94-8 isomeric mixture and 20324-32-7 major isomer) PM and PMA were reviewed at SIAM 11 and DPM was reviewed at SIAM 12. There are different methods to purify the UDD powders. The results show that the contact area between the blade and granite is not following a straight line, and the time required for stone sawing is only one half of the full sawing cycle. PGI is a colorless, water soluble, hygroscopic liquid with a characteristic glycol odor, medium viscosity, low vapor The ultra-dispersed diamond (UDD) powders were purchased from International Technology Centre, USA (http://www.itc-inc.org) with the following specifications: 98% purity, 510nm particle core size, cubic shape, grey color, 300400m2/g specific surface area. The Raman, TEM and XRD analysis was also performed on acid treated nanodiamond particles. The thermal performance of the internal heat transfer fluid was an important factor affecting the heat transfer efficiency of the exchanger system. derelict property for sale leicestershire,
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