In the heat exchanger, the hot fluid passes through the shell side and the cold fluid (nanofluid) passes through the helical coil side. Comparisons with data from literature confirmed the validity and the suitability of the nanoflash technique applied to thermal conductivity evaluation. WebPropylene glycol is a colourless liquid that is relatively viscous, has no odour, and tastes slightly sweet. 0000002335 00000 n 115-123, International Communications in Heat and Mass Transfer, Volume 76, 2016, pp. The authors would like to acknowledge the Portuguese Science and Technology Foundation (FCT) for the funding of the present research work through the grant no: PTDC/EME-MFE/105031/2008 (ACMS) and UID/EMS/00481/2013 (TEMA/DEM). The hybrid nanofluid presents intermediate values between those of the mono nanofluids for all the properties except dynamic viscosity. The purification of UDD powders is important for achieving good stable nanofluids. Effects of working temperature on thermo-physical properties and forced convection heat transfer of TiO 2 nanofluids in waterEthylene glycol mixture. Chemical treatment was used to make ND nanoparticles with an average size of 5.42nm. 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%. 0000115846 00000 n 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. Yu et al. Forced convection experiments were performed on an instrumented metal plate with micro-channels. Effects of heatlight source on the thermal efficiency of - Springer Sundar et al. 0000088556 00000 n [14,15] for mono nanofluids based on the same base fluid, propylene glycol:water 20:80 wt%. The purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. 0000089466 00000 n 0000033853 00000 n If you want to reproduce the whole article please go to the Copyright Clearance Center request page. Different weight or mass ratios of ethylene glycol/water (EG/W) or propylene glycol/water (PG/W) fluids are commonly used as engine coolants for automobile radiators and also used as coolant for electronic equipments, heating industrial and residential buildings in the cold countries of the world such as Alaska, Canada, Northern Europe and Russia, because of its low freezing point i.e. FPx[[cu/Ajl22jw+x{5DD93o9$C y6q`xTu/~:'KY'Nf700zGRb9 cyI/ dk'Cw JO|i%H_o]*2?h1tz{]uhD5:h;)[.2sQvW |ZHcv7Qcr9]Ee5c w?a%2b5XATC3{d^Tzt h-!T`EH|}'EPj:]vRFl_/ uoDG0x5zUK;EI[".WzVkE=*j\2U]O sh`5 2 shows the IR spectra of UDD powders, acid treated, salt and sucrose milled samples. The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of EG/W mixture based Al2O3, CuO, ZnO and Fe3O4 nanofluids. The viscosity of N-CQDs nanofluid behaves as a Newtonian fluid. Namburu et al. [27] analysis if the value of C/Ck<4 then the nanofluid is heat transfer beneficial fluid. Thermophysical, rheological and electrical properties of Read more about how to correctly acknowledge RSC content. For 1.0% vol. The eccentric hinge guide mechanism facilitates the formation of both matrix tails on the segments and a group of more new micro cutting edges, which improve diamond stability as well as self-sharpening. in a third-party publication (excluding your thesis/dissertation for which permission is not required) Another method for removing the carbon impurities from the UDD powders is with dry salt or dry sucrose [10]. 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. WebDOWFROSTfluid is a formulation of 95.5 percent propylene glycol, dipotassium phosphate and water. 8 . WebThere are two main types of water glycol mixtures used in heating/cooling systems that mix well in water at any concentration. 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. Thereby, nanofluids have proven to be useful in applications, especially electronic cooling, where increasing thermal properties and avoiding electrical conductivity are vital. In this particular system we are using an expansion tank with a bladder, so we don't have a make-up pump. The purchased ultradispersed diamond (UDD) nanoparticles were treated with strong acid solution to make it into almost single nano-diamond (ND) particles. An enhancement of thermal conductivity with respect to temperature and volumetric concentration is found, as expected. 0000002101 00000 n These values are significantly larger than that of the marble frame saw. 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. [34], in which the nanofluids prepared in pure PG have lower thermal conductivity enhancement than that of. The Wilson plot method is used to analyze the helical coil side heat transfer coefficients. If you are the author of this article, you do not need to request permission to reproduce figures 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 Tyler et al. 40-48, Applied Thermal Engineering, Volume 90, 2015, pp. Sundar et al. WebPropylene Glycol Methyl Ether (PM; CAS No. 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 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 About 26% increase in coolant side heat transfer coefficient was obtained with 2vol.% ZnOPG nanofluid under constant bath temperature condition which could be attributed to thermal conductivity enhancement as well as improved natural convection due to viscosity reduction. [25], [26] also prepared 20:80%, 40:60% and 60:40% EG/W based Fe3O4 nanofluids and measured both thermal conductivity and viscosity experimentally. The results of proposed models were compared to 23 well-known theoretical and empirical models. The effect of various factors on the thermal-physical properties of diamond nanofluids is also reviewed, and the stability and viscosity of diamond nanofluids are tabulated and compared. Electrical conductivity measurements of nanofluids and - PubMed 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). 181-190, International Journal of Heat and Mass Transfer, Volume 129, 2019, pp. Additionally, surface tension and electrical conductivity are investigated. The stability, thermophysical properties and rheological characteristics of N-CQDs nanofluids were investigated. How about a secondary heat exchanger, i.e primary steam/water heats intermediate water. Intemediate water is pumped to a secondary heat exchanger w Download : Download high-res image (216KB)Download : Download full-size image. 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. to access the full features of the site or access our, Joint School of Nanoscience and Nanoengineering, North Carolina A&T State University, Greensboro, NC 27401, USA, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC 27401, USA. Propylene glycol The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. 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. The formation of carboxyl (COOH) groups on the surface of nanodiamond was analyzed by FTIR. The thermal conductivity results here reported can be compared with those previously published by Sundar et al. 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. 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. Electrical conductivity of 50% glycol with inhibitors In addition, the models for estimating the viscosity and thermal conductivity of N-CQDs nanofluids are proposed, respectively. 11 is presented the percentage thermal conductivity enhancement [(knfkbf)/kbf100] for these ratios along with the data with the data of Palabiyik et al. electrical 0000017674 00000 n 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. Common uses: antifreeze/heat transfer fluid. The starting product, MICRONAL 5428 X, which contains about 43% microencapsulated paraffin with a transformation temperature of 28 108-65-6) Dipropylene Glycol Methyl Ether (DPM; CAS No. The earlier works reveal the preparation, estimation of thermal conductivity and viscosity of water, ethylene glycol, mineral oil and midel oil based ND nanofluids. Increasing the concentration of the nanofluid beyond 1.0vol% shows a little improvement in the effectiveness of the heat exchanger. 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). and diagrams provided correct acknowledgement is given. Copyright 2023 Elsevier B.V. or its licensors or contributors. 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 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. Interactions between spherical and sheet-like nanoparticles explain this behaviour. 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. The present findings are consistent with those of Palabiyik et al. 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. Water-Glycol mixture measurement | Baker Hughes An enhancement of 4.24% in heat transfer rate was observed with 2vol.% ZnOPG nanofluid. The thermal performance of the internal heat transfer fluid was an important factor affecting the heat transfer efficiency of the exchanger system. BNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. In this study, the thermal conductivity of graphene/propylene glycol nanofluids is tested using the Hot Disk TPS-500S thermal constants analyzer (Hot Disk AB, Gteborg, Sweden). V.C.1 Complex Coolant Fluid for PEM Fuel Cells - Energy The electrical conductivity of glycol mixtures within the range of Propylene Glycol Ethers Liquids - Thermal Conductivities - Engineering ToolBox Copyright Clearance Center request page. The acid treated ND particles were characterized by XRD, TEM, FTIR and XPS. 0000088822 00000 n The carbon impurities present in the UDD powders have been removed using mixture of H2SO4 and HNO3 [5], [6], [7], [8], [9]. 0000087804 00000 n startxref The single phase heat transfer fluids such as water (W), ethylene glycol (EG), propylene glycol (PG) and engine oil (EO) are primarily used in may industrial applications, among others, power, chemical and food industries. %PDF-1.6 % 499-508, Energy Conversion and Management, Volume 96, 2015, pp. Our results indicate that the surfactant-free, ZnOPG nanofluids behave like liquid coolants but with improved thermal conductivity and specific heat and hence suitable for energy management. [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. [18] observed thermal conductivity enhancements of 7.2% and 9.8% for water based ND nanofluids at 3.0vol.% at temperatures of 30C and 50C, respectively. This paper reviews and summarizes the experimental values of the physical and thermal properties, including an appropriate focus on the thermal conductivity enhancement, of nanodiamond-nanofluid systems found in the literature as well as different techniques for thermal conductivity measurement. The fluid is colorless (water white). 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. 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. conductivity of propylene glycol The thermal conductivity and viscosity of ND nanofluids were investigated experimentally, whereas the density and specific heat were estimated theoretically. The rheological behaviour is investigated through rotational rheometry. Under constant heat flux conditions, ZnOPG nanofluids exhibited linear increase in heat removal rates with increasing nanoparticle concentration. 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. Here, we perform electrical characterizations of propylene glycol-based ZnO nanofluids with volume fractions as high as 7%, measuring up to a 100-fold increase in electrical conductivity over the base fluid. Therefore, there is no literature on the thermal properties of PG/W mixture based ND nanofluids. Xu X, Choi SUS. 0000142997 00000 n 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. Electrical Thus, the new prototype machine is suitable for sawing granite. Chemical co-precipitation was used for the synthesis of large quantity of Fe3O4 nanoparticles with an average particle size of 11.42nm. <50C [21]. 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 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 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. Similarly, the viscosity enhancements are 1.55-times, 1.50-times and 1.66-times for the same 1.0vol.% of 20:80%, 40:60% and 60:40% PG/W based nanofluids at a temperature of 60C, respectively compared to their respective base fluids. An investigation has been undertaken into the stone processing machines. The X-ray powder diffraction (XRD), transmission electron microscope (TEM) and Raman spectra was also performed on acid treated ND particles. The carbon impurities present in the UDD powders is removed with strong acid treatment, dry salt and dry sucrose to make them into single ND crystals. Xie et al. There have been numerous investigations of nanodiamond-nanofluid systems with many suggesting that considerable property enhancements, e.g., increased thermal conductivity, might be possible. <]>> 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. Drazen, you seem to have drifted from the original question. The problem is glycol in the condensate which could be fatal to the boiler. We need 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. 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. 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%. Yeganeh et al. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity. 0000125049 00000 n 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. 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 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. The propylene glycol/water mixtures at different weight ratios were used as base fluids for the preparation of stable ND nanofluids. [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. Conjugate heat transfer was found to reduce the Nusselt number which agrees with the literature, this also resulted in a Peclet number dependent Nusselt number. 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. 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%). Measuring glycol concentrations by electrical conductivity is not recommended, especially in process systems, heat exchangers, etc. The quality of The X-ray powder diffraction (XRD), transmission, C, respectively compared to their respective base fluids. 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. 2016 Elsevier B.V. All rights reserved. 0000102258 00000 n Accurate estimation of thermal conductivity (TC) of nanofluids is essential in thermophysical studies of nanofluids. 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. New friction factor and Nusselt number equations were created. Branson et al. 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. Reynolds numbers were in the range 10100 and fluid inlet temperatures ranged from 5 to 40C. The sensitivity analysis illustrated that temperature has the highest effect on the relative TC followed by base fluid TC and particle volume fraction. Conductivity 107-98-2) Propylene Glycol Methyl Ether Acetate (PMA; CAS No. The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. 0000000918 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. 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. 0000002832 00000 n The peak near 1630cm1 represents the OH bending of physically adsorbed water and the hydrogen, Since the literature does not report for the thermal conductivity ratios of 20:80%, 40:60% and 60:40% PG/W nanofluids, in Fig. trailer 0000003320 00000 n Islam, R.; Shabani, B. Pressure and temperature variation of the electrical conductivity of 0 0000086902 00000 n Webconductivity. It is hygroscopic, meaning that it readily absorbs water from the surrounding environment. Energy . The thermal conductivity of single phase heat transfer fluids may be enhanced by dispersing small quantity of solid particles. The thermodynamic, heat transfer and thermal performance factor were analyzed experimentally at different particle volume loadings of water+ethylene glycol mixture based nanodiamond (ND) nanofluids flow in a shell and helical coiled tube heat exchanger. 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. Joint School of Nanoscience and Nanoengineering, North Carolina A&T State University, Greensboro, NC 27401, USA You do not have JavaScript enabled. model and the Mouromtseff number were used to study the heat transfer capability of ND nanofluid under laminar and turbulent flow conditions. 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. [17] prepared mineral oil based ND nanofluids and obtained thermal conductivity enhancement of 70% at 0.1wt.%. 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. Fig. However, those results have not been collectively compared or discussed. The functional groups on the treated UDD powders were analyzed by FTIR. The inadequacy of the widely used VogelTammannFulcher or WilliamsLandelFerry equations to describe the temperature variation of the vacuum Nanofluids offer many opportunities to enhance the efficiency of thermal systems by improving the thermal properties of the host fluids. If you are an author contributing to an RSC publication, you do not need to request permission [34] for Al2O3/PG and TiO2/PG nanofluids. The synthesized environmentally friendly N-doped carbon quantum dots nanoparticles (N-CQDs) had a uniform particle size distribution, with particle sizes concentrated between 2 and 2.5nm. The preparation of ND based nanofluids and their thermal properties are given below. Scaling effects such as viscous dissipation and entrance effects had insignificant impact on the measured average Nusselt number. Prasher et al. The relative electrical conductivity of -SiC NFs and model predictions determined at 298.15 K are compared as illustrated in Fig. The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of PG/W mixture based Al2O3, CuO, and Fe3O4 nanofluids. Webviscosity, a relatively high specific heat and thermal conductivity, as well as good mixing with water and alcohols cause the ethylene glycol to be widely used in practice [13]. By continuing you agree to the use of cookies. A. O. Maselugbo, B. L. Sadiku and J. R. Alston, Group method of data handling (GMDH) and gene expression programming (GEP) as two white-box powerful models were used for modeling. Hybrid nanofluids aim to further improve the characteristics of mono nanofluids.
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