By continuing you agree to the use of cookies. 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 go to the Copyright Clearance Center request page. 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%. The thermal performance of the internal heat transfer fluid was an important factor affecting the heat transfer efficiency of the exchanger system. Nanodiamondwater nanofluids were prepared and estimated the thermal conductivity, viscosity and also estimated their potential use in heat transfer applications. PGI is a colorless, water soluble, hygroscopic liquid with a characteristic glycol odor, medium viscosity, low vapor 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 have been numerous investigations of nanodiamond-nanofluid systems with many suggesting that considerable property enhancements, e.g., increased thermal conductivity, might be possible. Check with Union Carbide or Dow as they manufacture glycols. I understand they do have a web site. The results of proposed models were compared to 23 well-known theoretical and empirical models. [34], in which the nanofluids prepared in pure PG have lower thermal conductivity enhancement than that of. MEG (Mono Ethylene Glycol) or C2H6O2. For 1.0% and a Reynolds number of 1454.4, the thermal performance factor is increased by 1.194-times above the basic fluid. WebBNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. Read more about how to correctly acknowledge RSC content. 1000W/mK and Young's modulus, high electrical resistivity, attractive optical characteristics, and excellent chemical stability and biocompatibility. 0000002832 00000 n 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 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. 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 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. Therefore, there is no literature on the thermal properties of PG/W mixture based ND nanofluids. 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. 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. Copyright Clearance Center request page. 0000073108 00000 n * 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. Sundar et al. 0000113197 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. Since water is seen as the golden standard in thermal conductivity, higher concentrations of ethylene glycol in a water solution will cause heat to pass through it slower, therefore, the lower the amount of ethylene glycol in the mixture, the more efficient it is at conducting heat. 0000087536 00000 n The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of PG/W mixture based Al2O3, CuO, and Fe3O4 nanofluids. 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. We use cookies to help provide and enhance our service and tailor content and ads. [27] analysis.knfkbf=1+Cknfbf=1+Cwhere, is the volume concentration, Ck and C are the thermal conductivity and viscosity enhancement coefficients. Copyright 2023 Elsevier B.V. or its licensors or contributors. 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. 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 Branson 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. 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. Interactions between spherical and sheet-like nanoparticles explain this behaviour. An investigation has been undertaken into the stone processing machines. One of the authors (L.S.S.) It was observed that the position of the thermocouples can result in an under-estimation of the Nusselt number. 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. 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%. <50C [21]. 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. New friction factor and Nusselt number equations were created. 0000115846 00000 n 0000086902 00000 n 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. [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 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%. 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 The specific heat capacity decreases with increasing nanofluid loading. Webconductivity. Forget about conductivity, it is directly related to temperature and is used in domestic/process water systems (water treatment) where you don't ha 209 0 obj<>stream 0000087804 00000 n 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. Prasher et al. 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 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. 499-508, Energy Conversion and Management, Volume 96, 2015, pp. You do not have JavaScript enabled. 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. 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. From the Prasher et al. Reynolds numbers were in the range 10100 and fluid inlet temperatures ranged from 5 to 40C. This paper investigates the significance of some micro scaling effects in micro-channel absorber plates. 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. Yeganeh et al. startxref 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 purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. WebConductivity is a measure of the ability of water to pass an electrical current. However, those results have not been collectively compared or discussed. Results showed that ND nanofluids achieved higher heat transfer coefficients than the base fluid. 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). 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). 0000133274 00000 n The findings suggest that BNNBs have great potential for use as thermally conductive nanoparticles in nanofluids for various heat transfer applications. Xie et al. 0000088462 00000 n p^h72n* 8pW&.=rfeK&=d_">!f4-6%)|Z>,^R :qz*jn88H1 Z'2P?[-ik,2T0!L How about a secondary heat exchanger, i.e primary steam/water heats intermediate water. Intemediate water is pumped to a secondary heat exchanger w Chemical co-precipitation was used for the synthesis of large quantity of Fe3O4 nanoparticles with an average particle size of 11.42nm. 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%). 0000089466 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. [25], [26] also prepared 20:80%, 40:60% and 60:40% EG/W based Fe3O4 nanofluids and measured both thermal conductivity and viscosity experimentally. Experiments were performed to study the transient heat transfer characteristics of probe-ultrasonicated, surfactant-free, ZnOpropylene glycol (ZnOPG) nanofluids under constant heat flux and constant bath temperature conditions. Based on the above methods the acid treatment method is more effective compared to other salt and sucrose methods. Increasing the concentration of the nanofluid beyond 1.0vol% shows a little improvement in the effectiveness of the heat exchanger. 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. Properties for Dowfrost (Propylene Glycol) Electrical conductivity for 50% at 25 deg C = 2,060 micromhos/cm and 249 micromhos/cm for 50% at 0 deg C. Looks 180 0 obj <> endobj 0000073219 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. New thermal conductivity and viscosity correlations were proposed by including the effects of volume concentrations and temperatures. 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]. If you are the author of this article, you do not need to request permission to reproduce figures Appl. The main advantages of this measurement technique are short measurement times, easy sample preparation and high accuracy. endstream endobj 181 0 obj<. [34] for Al2O3/PG and TiO2/PG nanofluids. Comparisons with data from literature confirmed the validity and the suitability of the nanoflash technique applied to thermal conductivity evaluation. 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 0000002234 00000 n 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. Effects of working temperature on thermo-physical properties and forced convection heat transfer of TiO 2 nanofluids in waterEthylene glycol mixture. 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%. [19] obtained viscosity enhancement of 80% for midel oil based ND nanofluids at 3.0wt.%. This study investigates theoretically and experimentally the electrical and thermal conductivities of 50/50 water-ethylene glycol based TiO 2 nanofluids with 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 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 two-step approach was used to create ND nanofluids with volume concentrations ranging from 0.2% to 1.0%. 0000142997 00000 n WebPropylene Glycol Methyl Ether (PM; CAS No. 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# Tyler et al. The X-ray powder diffraction (XRD), transmission, C, respectively compared to their respective base fluids. 8 . E-mail: The present work shows an innovative frame saw machine to cut granite, the eccentric hinge guide mechanism is introduced into the machine. 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 heat transfer capability of these single phase heat transfer fluids is limited because of its poor thermal conductivity. All were assigned as low priority for further work. 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. 181-190, International Journal of Heat and Mass Transfer, Volume 129, 2019, pp. Energy . A. O. Maselugbo, B. L. Sadiku and J. R. Alston, 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. These values are significantly larger than that of the marble frame saw. Among all the carbon materials ND particles creates great interest because of their superior hardness, thermal conductivity, i.e. Glycol soutions are fed (topped-off) buy a pumped glycol feeder available by JL wingert, armstrong, etc Heat exchanger tubes are .035" wall I've ne An enhancement of 4.24% in heat transfer rate was observed with 2vol.% ZnOPG nanofluid. 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. 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. Accurate estimation of thermal conductivity (TC) of nanofluids is essential in thermophysical studies of nanofluids. [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. would like to thank FCT for his post-doctoral research grant: SFRH/BPD/79104/2011. The thermal conductivity results here reported can be compared with those previously published by Sundar et al. 0000002868 00000 n However, conjugate heat transfer and measurement uncertainties were significant. [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 X-ray powder diffraction (XRD), transmission electron microscope (TEM) and Raman spectra was also performed on acid treated ND particles. 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 Corresponding authors, a 245-255, Applied Thermal Engineering, Volume 91, 2015, pp. The thermal conductivity and viscosity of ND nanofluids were estimated experimentally at different particle concentrations and temperatures. Nanoscale, 2023, Advance Article Hybrid nanofluids aim to further improve the characteristics of mono nanofluids. 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. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity. The results are beneficial for the design and operation of micro-channel absorber plates. BNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap.