The sensitivity analysis illustrated that temperature has the highest effect on the relative TC followed by base fluid TC and particle volume fraction. 0000113197 00000 n Conductivity The PG/W nanofluids are prepared with acid treated ND particles. The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. [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. 499-508, Energy Conversion and Management, Volume 96, 2015, pp. 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. Jee and Lee [11] used strong acids of H2SO4 and HNO3 in the molar ratio of 3:1 for the purification of UDD powders and observed the removal of carbon impurities. There are different methods to purify the UDD powders. The Raman, XRD and TEM analysis are also used on UDD and ND-acid treated nanoparticles. Increasing the concentration of the nanofluid beyond 1.0vol% shows a little improvement in the effectiveness of the heat exchanger. 0 This paper presents results of experimental investigation into dielectric properties of silicon oxide lignin (SiO 2-L) particles dispersed with various mass fractions in ethylene glycol (EG).Measurements were conducted at a controlled temperature, which was changed from 298.15 to 333.15 K with an accuracy of 0.5 and 0.2 K for dielectric 0000088556 00000 n 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. The purchased ultradispersed diamond (UDD) nanoparticles were treated with strong acid solution to make it into almost single nano-diamond (ND) particles. 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. You do not have JavaScript enabled. 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 <50C [21]. 0000047379 00000 n It is hygroscopic, meaning that it readily absorbs water from the surrounding environment. The rheological behaviour is investigated through rotational rheometry. Sundar et al. The article presents the results of detailed studies of the thermal conductivity of the water slurry of microencapsulated PCM (mPCM) and slurry based on waterpropylene glycol solutions. 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. Forced convection experiments were performed on an instrumented metal plate with micro-channels. 0000060250 00000 n In addition, the models for estimating the viscosity and thermal conductivity of N-CQDs nanofluids are proposed, respectively. Copyright Clearance Center request page. Ghazvini et al. 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 Prasher 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. Propylene Glycol Ethers The purification of UDD powders is important for achieving good stable nanofluids. xref DOWFROSTfluid has an operating Branson et al. In addition, both cutting efficiency and slab flatness were recorded. 0000086902 00000 n The theoretical models of Maxwell and Einstein have failed to estimate the thermal conductivity and viscosity of nanofluids as a function of temperature. 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 functional groups on the treated UDD powders were analyzed by FTIR. On the other hand preparation of propylene glycol/water (PG/W) based nanofluids and estimation of thermal properties is also important before use in heat transfer equipments, because these PG/W fluids are also used as engine coolants for automobile radiators. The earlier works reveal the preparation, estimation of thermal conductivity and viscosity of water, ethylene glycol, mineral oil and midel oil based ND nanofluids. New thermal conductivity and viscosity correlations have been developed based on the experimental data. 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. WebDOWFROSTfluid is a formulation of 95.5 percent propylene glycol, dipotassium phosphate and water. * [34], in which the nanofluids prepared in pure PG have lower thermal conductivity enhancement than that of. Energy . 0000102258 00000 n The viscosity of N-CQDs nanofluid behaves as a Newtonian fluid. For 1.0% vol. conductivity WebThere are two main types of water glycol mixtures used in heating/cooling systems that mix well in water at any concentration. 0000033853 00000 n 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. The acid treated ND particles were characterized by XRD, TEM, FTIR and XPS. 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. Read more about how to correctly acknowledge RSC content. WebBNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. 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. The Raman, TEM and XRD analysis was also performed on acid treated nanodiamond particles. 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 of propylene glycol Complex Coolant Fluid for PEM Fuel Substance and % by volume in mixture: Minimal working temperature [o C] 40-48, Applied Thermal Engineering, Volume 90, 2015, pp. One of the authors (L.S.S.) , DOI: 10.1039/D2NR06332H. Xu X, Choi SUS. 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 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. 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 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. Naik and Sundar [28] prepared 30:70% PG/W based CuO nanofluid and estimated thermal conductivity and viscosity experimentally. %%EOF Electrical and Thermal Conductivities of 50/50 Water WebConductivity is a measure of the ability of water to pass an electrical current. ScienceDirect is a registered trademark of Elsevier B.V. ScienceDirect is a registered trademark of Elsevier B.V. 2023, Thermal Science and Engineering Progress, 2023, International Journal of Thermal Sciences, 2022, International Communications in Heat and Mass Transfer, Diamond and Related Materials, Volume 69, 2016, pp. Accurate estimation of thermal conductivity (TC) of nanofluids is essential in thermophysical studies of nanofluids. 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 New friction factor and Nusselt number equations were created. Propylene glycol Annual production of propylene glycol in The starting product, MICRONAL 5428 X, which contains about 43% microencapsulated paraffin with a transformation temperature of 28 and diagrams provided correct acknowledgement is given. 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. This study reports a nanofluid that achieves long-term stability without any additives. [27] analysis.knfkbf=1+Cknfbf=1+Cwhere, is the volume concentration, Ck and C are the thermal conductivity and viscosity enhancement coefficients. 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]. 0000000016 00000 n Prasher et al. [14,15] for mono nanofluids based on the same base fluid, propylene glycol:water 20:80 wt%. 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 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. How about a secondary heat exchanger, i.e primary steam/water heats intermediate water. Intemediate water is pumped to a secondary heat exchanger w The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. Another method for removing the carbon impurities from the UDD powders is with dry salt or dry sucrose [10]. The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of PG/W mixture based Al2O3, CuO, and Fe3O4 nanofluids. This study investigates theoretically and experimentally the electrical and thermal conductivities of 50/50 water-ethylene glycol based TiO 2 nanofluids with Thermophysical, rheological and electrical properties of Ethylene Glycol / Water Mixture Properties - CORECHEM Inc. Check with Union Carbide or Dow as they manufacture glycols. I understand they do have a web site. 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). 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%). PureCool LEC-PG Low Conductivity Heat Transfer Fluid WebPropylene glycol is a colourless liquid that is relatively viscous, has no odour, and tastes slightly sweet. 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. However, conjugate heat transfer and measurement uncertainties were significant. Electrical conductivity measurements of nanofluids and - PubMed . 0000142997 00000 n 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. It was observed that the position of the thermocouples can result in an under-estimation of the Nusselt number. The stability, thermophysical properties and rheological characteristics of N-CQDs nanofluids were investigated. Chemical co-precipitation was used for the synthesis of large quantity of Fe3O4 nanoparticles with an average particle size of 11.42nm. 1000W/mK and Young's modulus, high electrical resistivity, attractive optical characteristics, and excellent chemical stability and biocompatibility. Interactions between spherical and sheet-like nanoparticles explain this behaviour. 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. 0000017674 00000 n 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). Scaling effects such as viscous dissipation and entrance effects had insignificant impact on the measured average Nusselt number. 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. Namburu et al. The heat transfer capability of these single phase heat transfer fluids is limited because of its poor thermal conductivity. An estimation of the optimal supplied energy and time for sonication was suggested, while temperature and volumetric concentration effects on thermal conductivity are evaluated by measurements. 11 is presented the percentage thermal conductivity enhancement [(knfkbf)/kbf100] for these ratios along with the data with the data of Palabiyik et al. 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. The preparation of ND based nanofluids and their thermal properties are given below. Table 8-3-1 - Properties of mixture Water/Glycol - CERN The thermal conductivity and viscosity of ND nanofluids were investigated experimentally, whereas the density and specific heat were estimated theoretically. 209 0 obj<>stream Sundar et al. 245-255, Applied Thermal Engineering, Volume 91, 2015, pp. 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%. 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. 2 shows the IR spectra of UDD powders, acid treated, salt and sucrose milled samples. Based on the results, the thermal conductivity enhancements are 18.8%, 16.8% and 14.1% at 1.0 vol.% of 20:80%, 40:60% and 60:40% PG/W based nanofluids. WebPGI is a distilled product with a purity specification of minimum 99.5% and is available from The Dow Chemical Company in drum, IBC and bulk quantities. Download : Download high-res image (216KB)Download : Download full-size image. 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 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. The thermal conductivity results here reported can be compared with those previously published by Sundar et al. 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. Measuring glycol concentrations by electrical conductivity is not recommended, especially in process systems, heat exchangers, etc. The quality of All were assigned as low priority for further work. 107-98-2) Propylene Glycol Methyl Ether Acetate (PMA; CAS No. Copyright 2023 Elsevier B.V. or its licensors or contributors. A shell and helically coil heat exchanger (SCHE) is used to experimentally investigate the performance of 60% water and 40% ethylene glycol mixture based Fe3O4 nanofluid as a coolant. Forget about conductivity, it is directly related to temperature and is used in domestic/process water systems (water treatment) where you don't ha Tyler et al. 0000088462 00000 n 0000002234 00000 n The different weight ratios of propylene glycol/water mixtures are used as base. 0000003207 00000 n The exergy analysis and heat transfer characteristics pertaining to the heat exchanger were also investigated. WebLearn about the chemical and physical properties of Ethylene Glycol/water mixtures, on our blog. 0000087536 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. Please enable JavaScript 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. 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. If you are the author of this article, you do not need to request permission to reproduce figures conductivity of propylene glycol
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