Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases. WebDOWFROSTfluid is a formulation of 95.5 percent propylene glycol, dipotassium phosphate and water. of nanofluid, the exergy efficiency is 22.97%, while for ethylene glycol, it is 6.78%. An enhancement of 4.24% in heat transfer rate was observed with 2vol.% ZnOPG nanofluid. jralston1@ncat.edu, b Appl. 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]. The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. FROZKHQ KHDWHGLQWKH+9HOHFWULFILHOG endstream endobj 181 0 obj<. The findings suggest that BNNBs have great potential for use as thermally conductive nanoparticles in nanofluids for various heat transfer applications. 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 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. 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. 181-190, International Journal of Heat and Mass Transfer, Volume 129, 2019, pp. WebLearn about the chemical and physical properties of Ethylene Glycol/water mixtures, on our blog. Pressure and temperature variation of the electrical conductivity of New thermal conductivity and viscosity correlations have been developed based on the experimental data. Please enable JavaScript The functional groups on the treated UDD powders were analyzed by FTIR. 245-255, Applied Thermal Engineering, Volume 91, 2015, pp. %PDF-1.6 % Liquids - Thermal Conductivities - Engineering ToolBox The propylene glycol/water mixtures at different weight ratios were used as base fluids for the preparation of stable ND nanofluids. The viscosity of N-CQDs nanofluid behaves as a Newtonian fluid. Electrical conductivity measurements of nanofluids and - PubMed 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. New thermal conductivity and viscosity correlations have been developed based on the experimental data. 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. 115-123, International Communications in Heat and Mass Transfer, Volume 76, 2016, pp. 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. Correlations for the thermo-physical properties of the nanofluid were developed. 2 shows the IR spectra of UDD powders, acid treated, salt and sucrose milled samples. 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. [34] for Al2O3/PG and TiO2/PG nanofluids. The purchased ultradispersed diamond (UDD) nanoparticles were treated with strong acid solution to make it into almost single nano-diamond (ND) particles. The formation of carboxyl (COOH) groups on the surface of ND particles was analyzed by FTIR spectrum. The heat transfer capability of these single phase heat transfer fluids is limited because of its poor thermal conductivity. [17] prepared mineral oil based ND nanofluids and obtained thermal conductivity enhancement of 70% at 0.1wt.%. V.C.1 Complex Coolant Fluid for PEM Fuel Cells - Energy 107-98-2) Propylene Glycol Methyl Ether Acetate (PMA; CAS No. 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. 0000000918 00000 n Sundar et al. Annual production of propylene glycol in They also observed the formation of carboxyl groups on the surface of ND particles based on the FTIR analysis. 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. DOWFROSTfluid has an operating If you are the author of this article, you do not need to request permission to reproduce figures 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]. startxref PGI is a colorless, water soluble, hygroscopic liquid with a characteristic glycol odor, medium viscosity, low vapor 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. The sensitivity analysis illustrated that temperature has the highest effect on the relative TC followed by base fluid TC and particle volume fraction. 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. The purchased UDD powders treated with strong acid treatment, dry salt and dry sucrose to make them into single ND-crystals. Nanodiamondwater nanofluids were prepared and estimated the thermal conductivity, viscosity and also estimated their potential use in heat transfer applications. The X-ray powder diffraction (XRD), transmission electron microscope (TEM) and Raman spectra was also performed on acid treated ND particles. The earlier works reveals the preparation, estimation of thermal conductivity and viscosity of EG/W mixture based Al2O3, CuO, ZnO and Fe3O4 nanofluids. The exergy analysis and heat transfer characteristics pertaining to the heat exchanger were also investigated. The results of proposed models were compared to 23 well-known theoretical and empirical models. electrical 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. 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. 0000088556 00000 n 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 hybrid nanofluid presents intermediate values between those of the mono nanofluids for all the properties except dynamic viscosity. In the heat exchanger, the hot fluid passes through the shell side and the cold fluid (nanofluid) passes through the helical coil side. Substance and % by volume in mixture: Minimal working temperature [o C] Webconductivity. 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. 180 0 obj <> endobj We use cookies to help provide and enhance our service and tailor content and ads. Scaling effects such as viscous dissipation and entrance effects had insignificant impact on the measured average Nusselt number. The theoretical models of Maxwell and Einstein have failed to estimate the thermal conductivity and viscosity of nanofluids as a function of temperature. Forced convection experiments were performed on an instrumented metal plate with micro-channels. BNNBs exhibit high thermal conductivity due to efficient phonon transfer and they are electrical insulators owing to their wide bandgap. 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. [30] also prepared 20:80%, 40:60% PG/W based Fe3O4 nanofluids and estimated thermal conductivity and viscosity experimentally. The two-step approach was used to create ND nanofluids with volume concentrations ranging from 0.2% to 1.0%.
Willamette National Cemetery Obituaries,
Andrew Richardson Son Tennis,
Flows Definition Ap Human Geography Unit 1,
Articles E