One of the authors (L.S.S.) [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. 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. Sundar et al. [14,15] for mono nanofluids based on the same base fluid, propylene glycol:water 20:80 wt%. 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. Interactions between spherical and sheet-like nanoparticles explain this behaviour. The starting product, MICRONAL 5428 X, which contains about 43% microencapsulated paraffin with a transformation temperature of 28 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. The Raman, XRD and TEM analysis are also used on UDD and ND-acid treated nanoparticles. 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. k5fX.TX#HksQ} >6!"vg8{!SP/(b8#_"hr 1q"I}\gxu'Gxq`j^vGF`i R7`md\qM._8>)pbE.x%6s&Eg)c^mDO1 }rZ~&\!=[aHM3]qIvT=nD{vf!oSAc0T]z4J0({(YxkyCWboRycfP'{ug04tTS[eun-8'$Q)^U/+jkaIB@^%BX# 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 ). Results showed that ND nanofluids achieved higher heat transfer coefficients than the base fluid. The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. 115-123, International Communications in Heat and Mass Transfer, Volume 76, 2016, pp. 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. 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. startxref Energy . WebLearn about the chemical and physical properties of Ethylene Glycol/water mixtures, on our blog. The X-ray powder diffraction (XRD), transmission electron microscope (TEM) and Raman spectra was also performed on acid treated ND particles. However, conjugate heat transfer and measurement uncertainties were significant. An enhancement of thermal conductivity with respect to temperature and volumetric concentration is found, as expected. Pressure and temperature variation of the electrical conductivity of The thermal conductivity and viscosity of ND nanofluids were investigated experimentally, whereas the density and specific heat were estimated theoretically. 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. WebThere are two main types of water glycol mixtures used in heating/cooling systems that mix well in water at any concentration. Progress and Perspectives of Lithium Aluminum Germanium The Prasher et al. In addition, both cutting efficiency and slab flatness were recorded. 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. Conductivity 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. Prediction of electrical conductivity of TiO 2 water and ethylene glycol-based nanofluids for cooling application in low temperature PEM fuel cells. Annual production of propylene glycol in Corresponding authors, a These plates are to be used in a proposed compact (thin and light-weight) solar thermal flat plate collector (FPC). Yu et al. 8 . 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 preparation of ND based nanofluids and their thermal properties are given below. The Wilson plot method is used to analyze the helical coil side heat transfer coefficients. All were assigned as low priority for further work. In this particular system we are using an expansion tank with a bladder, so we don't have a make-up pump. 181-190, International Journal of Heat and Mass Transfer, Volume 129, 2019, pp. 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 Islam, R.; Shabani, B. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity. [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. When compared to Propylene glycolwater (50:50) along with Propylene glycolwater (50:50) dispersed with 0.25% Graphene, it is clear from Fig. 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. Diamond circular saws and diamond wire saws present some technological limits, and the marble frame saw cannot process granite by now. Electrical Conductivity and Dielectric Properties 0000087804 00000 n 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 , DOI: 10.1039/D2NR06332H. 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. endstream endobj 181 0 obj<. 0000033853 00000 n 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. Check with Union Carbide or Dow as they manufacture glycols. I understand they do have a web site. 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. Branson et al. The UDD powders can be treated with strong acids such as HNO3, mixture of H2SO4/HNO3, K2Cr2O7 in H2SO4, KOH/KNO3 to remove the carbon impurities [3], [4]. 2 shows the IR spectra of UDD powders, acid treated, salt and sucrose milled samples. 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. There are different methods to purify the UDD powders. of nanofluid, the exergy efficiency is 22.97%, while for ethylene glycol, it is 6.78%. The thermal conductivity results here reported can be compared with those previously published by Sundar et al. [19] obtained viscosity enhancement of 80% for midel oil based ND nanofluids at 3.0wt.%. 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. WebConductivity is a measure of the ability of water to pass an electrical current. 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. The thermal conductivity of 0.1vol% of N-CQDs nanofluid increased by 43.21% at 50C compared to the base fluid. The acid treated ND particles were characterized by XRD, TEM, FTIR and XPS. However, experimental studies that jointly explore the physical properties of hybrids and the corresponding mono nanofluids are missing. 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. %%EOF Investigation on the Electrical Conductivity of The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. 0000086285 00000 n 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. 0000125049 00000 n Effects of heatlight source on the thermal efficiency of - Springer 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. Xu X, Choi SUS. The low freezing point of water (below 0C) may be achieved by adding different ratios of ethylene glycol or propylene glycol, so that the EG/W or PG/W fluid can operate up to 50C without any difficult [22]. Based on the above methods the acid treatment method is more effective compared to other salt and sucrose methods. WebDOWFROSTfluid is a formulation of 95.5 percent propylene glycol, dipotassium phosphate and water. 0000115846 00000 n 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. How about a secondary heat exchanger, i.e primary steam/water heats intermediate water. Intemediate water is pumped to a secondary heat exchanger w Engineering and Operating Guide for Dowfrost and Dowfrost HD 0000003320 00000 n The earlier works reveal the preparation, estimation of thermal conductivity and viscosity of water, ethylene glycol, mineral oil and midel oil based ND nanofluids. Among all the carbon materials ND particles creates great interest because of their superior hardness, thermal conductivity, i.e. 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 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 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. New thermal conductivity and viscosity correlations were proposed by including the effects of volume concentrations and temperatures. 0000002335 00000 n Correlations for the thermo-physical properties of the nanofluid were developed. E-mail: 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%. For 1.0% vol. . [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 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 results of proposed models were compared to 23 well-known theoretical and empirical models. 209 0 obj<>stream WebPropylene Glycol Methyl Ether (PM; CAS No. conductivity of propylene glycol They obtained increases of 10.4% and 9.9% for 0.5 vol% concentration of Fe3O4 [14] and 1 vol% concentration of nanodiamonds [15] at 293.15 K, respectively. 2016 Elsevier B.V. All rights reserved. [27] analysis.knfkbf=1+Cknfbf=1+Cwhere, is the volume concentration, Ck and C are the thermal conductivity and viscosity enhancement coefficients. Scaling effects such as viscous dissipation and entrance effects had insignificant impact on the measured average Nusselt number. New friction factor and Nusselt number equations were created. V.C.1 Complex Coolant Fluid for PEM Fuel Cells - Energy Prasher et al. The stability, thermophysical properties and rheological characteristics of N-CQDs nanofluids were investigated. Electrical conductivity measurements of nanofluids and - PubMed 0000088556 00000 n 0000133274 00000 n The rheological behaviour is investigated through rotational rheometry. 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 frictional exergy destruction is found to contribute together with heat transfer exergy destruction to the total entropy of the SCHE system. If you are an author contributing to an RSC publication, you do not need to request permission New thermal conductivity and viscosity correlations have been developed based on the experimental data. 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 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 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. To request permission to reproduce material from this article, please go to the Water-Glycol mixture measurement | Baker Hughes Ethylene Glycol / Water Mixture Properties - CORECHEM Inc. Propylene Glycol Ethers There have been numerous investigations of nanodiamond-nanofluid systems with many suggesting that considerable property enhancements, e.g., increased thermal conductivity, might be possible. Nanodiamondwater nanofluids were prepared and estimated the thermal conductivity, viscosity and also estimated their potential use in heat transfer applications. 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. 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. The specific heat capacity decreases with increasing nanofluid loading. jralston1@ncat.edu, b By continuing you agree to the use of cookies. The two-step approach was used to create ND nanofluids with volume concentrations ranging from 0.2% to 1.0%. Under constant heat flux conditions, ZnOPG nanofluids exhibited linear increase in heat removal rates with increasing nanoparticle concentration. 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. 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%. 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. Table 8-3-1 - Properties of mixture Water/Glycol - CERN The thermal conductivity of single phase heat transfer fluids may be enhanced by dispersing small quantity of solid particles. For reliability, Electrical conductivity of aqueous Propylene glycol (PG/W-30/70) is determined (30EG/70W) as a for three times and the same is compared with The Choi [1] and his team developed nanofluids (fluids contain nanometer size particles) and obtained higher thermal conductivity compared to base fluids. <50C [21]. 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. 0000088462 00000 n The overall heat transfer coefficient and nanofluid-side heat transfer coefficient under constant bath temperature condition were found to increase with increasing nanoparticle volume concentration. 5. The purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. Copyright 2023 Elsevier B.V. or its licensors or contributors. 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 and diagrams provided correct acknowledgement is given. xref of Propylene Glycol Chemical treatment was used to make ND nanoparticles with an average size of 5.42nm. Group method of data handling (GMDH) and gene expression programming (GEP) as two white-box powerful models were used for modeling. The purification of UDD powders is important for achieving good stable nanofluids. Forget about conductivity, it is directly related to temperature and is used in domestic/process water systems (water treatment) where you don't ha Electrical and Thermal Conductivities of 50/50 Water Thereby, nanofluids have proven to be useful in applications, especially electronic cooling, where increasing thermal properties and avoiding electrical conductivity are vital. Thus, the new prototype machine is suitable for sawing granite. Using propylene glycol (PG) without any dispersants as a salt-free medium, we measure the electrical conductivities of 20, 40, and 60 nm diameter ZnO nanoparticle dispersions up to 7% volume fraction, applying Ohshima's model to determine the limiting ionic conductance of the system. Nanofluid preparation and characterization Nanofluid preparation 180 0 obj <> endobj The commercially available ultra-dispersed diamond (UDD) powders of an average size of 0.12.0m have been used by Dolmatov [2] for the preparation of ND nanofluids, but he faced serious agglomeration problem with UDD powders in the base fluid. <]>> Measuring glycol concentrations by electrical conductivity is not recommended, especially in process systems, heat exchangers, etc. The quality of 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 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. This study reports a nanofluid that achieves long-term stability without any additives. Sundar et al. Tyler et al. 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. 0000142997 00000 n 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. 0000047379 00000 n This study investigates theoretically and experimentally the electrical and thermal conductivities of 50/50 water-ethylene glycol based TiO 2 nanofluids with Webconductivity. [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. [34] for Al2O3/PG and TiO2/PG nanofluids. The functional groups on the treated UDD powders were analyzed by FTIR. Sundar et al. 0000102258 00000 n 0000060250 00000 n of propylene glycol 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). 0000003035 00000 n An investigation has been undertaken into the stone processing machines. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases. 11 is presented the percentage thermal conductivity enhancement [(knfkbf)/kbf100] for these ratios along with the data with the data of Palabiyik et al. 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.