Nanofluids, the fluid suspensions of nanomaterials, have shown many interesting properties, and the distinctive features offer unprecedented potential for many applications. Aug 16, 2011 migration of carbon nanotubes from liquid phase to vapor phase in the refrigerant based nanofluid pool boiling. Similarly nanoparticles can be added to the refrigerant and the refrigerant nanoparticles mixture is known as nanorefrigerant. There has been increasing interest of late in nanofluid boiling and its use in heat transfer enhancement. Water based al 2 o 3 and diamond nanofluids were applied in the minimum quantity lubrication mql grinding process of cast iron. Yuchoi model21 is another static mechanism based model and is a renovated form of the maxwell model. Thermophysical properties of twophase refrigerant based nanofluids in a refrigeration cycle. Similar to the refrigerant based nanofluids without lubricants, they developed a new model reflecting the influences of refrigerant based nanofluid composition and heating condition on the migration characteristics of nanoparticles.
Nanolayer and nanoconvection based enhanced thermal. The additive used in the mineral oil based lubricant was tio2 nanoparticles. Pdf nanofluid as a heat transfer fluid has been gaining popularity. Pdf analysis of working nanofluids for a refrigeration system.
Advantages and disadvantages of nanofluid implementation in condensing and. Review of the thermophysical properties and performance. Pressure drop characteristics by using nanofluids in a simple system also have been investigated. R718 water is used as a secondary refrigerant in refrigeration systems. Thermal conductivity, viscosity, and density of the nanofluids were increased, but the specific heat of the nanofluids was decreased with increasing the concentrations of the particles. An extensive experimental investigation on the thermophysical properties of two different types of r718 water based nanofluid was performed for particle volume fractions. Thermal conductivity, viscosity and density of r141b refrigerant based nanofluid i. The migration characteristics of carbon nanotubes from liquid phase to vapor phase in the refrigerantbased nanofluid pool boiling were investigated experimentally. Analysis of working nanofluids for a refrigeration. Theoretical investigation of the thermophysical properties of. Nano idea open access migration of carbon nanotubes from. Refrigerantbased nanofluids are termed as nanorefrigerants, which are capable of improving the performance of refrigeration systems. Performance analysis of a refrigeration system using nano fluid 461 there is the significant increase in the thermal conductivity of nanofluid when compared to the base fluid and also found that addition of nanoparticles results in significant increase in the critical heat flux.
Flowboiling of r4apoecuo nanofluids in a horizontal tube. In splittype domestic air conditioner, r22 is used as refrigerant and a shell and coil type heat exchanger sche intercooler is employed. Optimal performance analysis of energy efficient residential. Refrigerants act as coolants due to their low boiling temperature. This paper summarizes the recent progress on the study of nanofluids, such as the preparation methods, the evaluation methods for the stability of nanofluids, and the ways to enhance the stability for nanofluids, the. Experimental investigation of thermophysical properties of. Pdf this paper presents the analysis of nanorefrigerant fluids to. The convective heat transfer coefficient was found to be 215 % higher than that of water at 50 kg. Influence of nanoparticle type, size and weight on. Heat pipe long term performance using water based nanofluid mohamed i. Similar to the refrigerantbased nanofluids without lubricants, they developed a new model reflecting the influences of refrigerantbased nanofluid composition and heating condition on the migration characteristics of nanoparticles. Boiling and twophase flow phenomena of refrigerantbased. Cfdentropy generation analysis of refrigerantbased nanofluids.
The experimental facility for testing the heat transfer characteristics of refrigerantbased nanofluid consists of a variablefrequency pump, a volume flow meter, a mixing chamber, a preheater, a test section, a cool water bath and a device for the charge of refrigerantbased nanofluid. The migration of cnts from liquid phase to vapor phase in the refrigerant based nanofluid pool boiling can be divided to the following four physical processes. Cnts in the refrigerant based nanofluid pool boiling at different original cnts concentrations, and to propose a model for predicting the migration ratio of cnts in the refrigerant based nanofluid pool boiling. As already mentioned, the proposed model is only based on their own data. They summarized the correlations developed for heat transfer coef.
Pdf heat transfer improvement and pressure drop during. Controlling a multievaporator refrigeration system that uses. This makes it possible to use in the compressor for a long run. With the increasing awareness for energy saving and efficiency improvement in various thermal systems, including refrigeration systems, there is a growing interest in the refrigerant based nanofluids owing to their superior thermophysical properties. These fluids are engineered colloidal suspensions of nanoparticles in a base fluid. The heat pipe is a passive cooling device that transfers heat from a hot source to a heat sink using fluids as a working medium. The nanofluid is not just a liquidsolid mixture of the mineral oil and tio2. This article covers recent advances in the last decade by researchers in both pool boiling and convective boiling applications, with nanofluids as the working fluid. Performance evaluation of a shell and tube heat exchanger. The thickness of interfacial layer, tdepends on temperature where 0.
Mass transfer enhancement of nanofluids in a closed system. Heat transfer enhancement in domestic refrigerator using r600amineral oilnanoal 2 o 3. Abstractthe migration characteristics of carbon nanotubes from liquid phase to vapor phase in the. Migration of carbon nanotubes from liquid phase to vapor phase in the refrigerantbased nanofluid pool boiling. The thermal properties of r4abased nanofluids are measured.
The existing researches show that substituting refrigerant based nanofluid for conventional refrigerant is an effective method for improving the. Most of the nanofluids except pg brinebased al 2 o 3 ag nanofluid seem to be not beneficial for practical use due to comparatively long payback period. The thermal conductivity of nanorefrigerant is calculated by using data from table 2 and mathematical modeling from vasu et al. Nanorefrigerants are a class of nanofluid, which consist of. This article is from nanoscale research letters, volume 6. Based on the nanofluid refrigerantenhanced heat transfer enhanced seawater source heat pump heat exchanger, a testbed for improving. For enhancing the heat rejection on the condenser side, binary mixture of ethylene glycol and water based nanofluid is used as the shell side coolant. Migration of carbon nanotubes from liquid phase to vapor. However, it is not very practical when efficiencies of two fluids are compared in the same system geometry i.
The reasons for choosing tio 2 nanoparticles have been chosen because. Heat transfer enhancement in domestic refrigerator using r600amineral oilnanoal 2 o 3 as working fluid 1,r. Influences of refrigerantbased nanofluid composition and. Efficient aircondition unit by using nanorefrigerant. Heat pipe long term performance using water based nanofluid. It has been found out that the improvement in coefficient of performance cop is maximum 7. Four types of carbon nanotubes with the outside diameters from 15 to 80 nm and the lengths from 1. Suriyawong a, wongwises s 2010 nucleate pool boiling heat transfer characteristics of tio2water nanofluids at very low concentrations. The migration characteristics of carbon nanotubes from liquid phase to vapor phase in the refrigerant based nanofluid pool boiling were investigated experimentally.
Heat transfer characteristics of refrigerantbased nanofluid. Cnts in the refrigerantbased nanofluid pool boiling at different original cnts concentrations, and to propose a model for predicting the migration ratio of cnts in the refrigerantbased nanofluid pool boiling. Unit sections can be shipped split or split in the field without losing the factory charge resulting in no field brazing and a total installed cost. In this paper, experimental analysis is examined to estimate hydrothermal behavior of refrigerant based nanofluid nano refrigerant during condensation inside a horizontal tube. Common base fluids include water, ethylene glycol and oil. Nanolubricant refrigerant can be prepared by mixing pure refrigerant with nanolubricant. It must be stable and durable suspension with negligible agglomeration. Chloromethane r40, present in this counterfeit r4a, is found to be incompatible with aluminum. Nanofluids are considered a promising choice for several heat transfer applications. It is an ideal and unique reference source for scientists and engineers working in this important and emerging research field of science, engineering and technology. Copper oxide nanoparticles for advanced refrigerant. Pdf thermal conductivity, viscosity and density of r141b.
Conventional heat transfer fluids have inherently poor thermal conductivity. A lubricant based nanofluid is prepared with a synthetic ester and 30nm diameter cuo particles stably suspended in the mixture to a 4% volume fraction. Thermal conductivity, viscosity and density of r141b refrigerant based nanofluid. The thermal properties of r4a based nanofluids are measured. Request pdf influences of refrigerantbased nanofluid composition and heating condition on the migration of nanoparticles during pool boiling. The experimental facility for testing the heat transfer characteristics of refrigerant based nanofluid consists of a variablefrequency pump, a volume flow meter, a mixing chamber, a preheater, a test section, a cool water bath and a device for the charge of refrigerant based nanofluid. Narasimha 1,2,3,lecturer, school of mechanical and industrial engineering bahirdar university, bahirdar, ethiopia list of symbols symbol description unit nomenclature a cross sectional area m2 c p. Aluminium oxide nanofluid is used for enhancing the heat transfer capacity of the. Significant increases in viscosity, as high as 2147%, are observed due to cuo nanoparticles. Peng h, ding g, hu h 2011 effect of surfactant additives on nucleate pool boiling heat transfer of refrigerantbased nanofluid. Heat transfer enhancement in domestic refrigerator using.
These nanoparticles are dispersed in some hydrocarbonbased refrigerants, namely tetrafluoroethane r4a, propane r290, butane r600, isobutane. Nanofluids have novel properties that make them potentially useful. Experimental analysis of a refrigeration system using. Thermal conductivity, viscosity and density of r141b refrigerant based nanofluid article pdf available in procedia engineering 56. With the increasing awareness for energy saving and efficiency improvement in various thermal systems, including refrigeration systems, there is a growing interest in the refrigerantbased nanofluids owing to their superior thermophysical properties. Performance analysis of vcrs with nano refrigerant k. Only the ato nanofluid exhibited a decrease in the measured viscosity. The experimental facility for testing the heat transfer characteristics of refrigerantbased nanofluid consists of a variablefrequency pump, a volume flow meter, a mixing chamber, a preheater, a test section, a cool water bath and a device for the charge of refrigerant based nanofluid. The heat transfer coefficient and performance of the system were evaluated by using tk solver, using nano concentration 0 to 1%. Normally r12, r22, r600, r600a and 4a are used as a refrigerant. The present study reveals that the brinebased hybrid nanofluids. A lubricantbased nanofluid is prepared with a synthetic ester and 30nm diameter cuo particles stably suspended in the mixture to a 4% volume fraction. Split system refrigerant piping guide united coolair. Experiments test conditions and experimental objects test conditions are divided into five categories, as tabulated in table 1.
Thermal conductivity of a liquid is an important physical property that decides its heat transfer performance. Composition analysis of contaminated and counterfeit. Energyeconomic analysis of plate evaporator using brine. Nevertheless, literatures about thermophysical properties of refrigerant based nanofluids are still. The nanoparticles used in nanofluids are typically made of metals, oxides, carbides, or carbon nanotubes. Mar 14, 2011 the migration characteristics of carbon nanotubes from liquid phase to vapor phase in the refrigerantbased nanofluid pool boiling were investigated experimentally. Theoretical investigation of the thermophysical properties. Most of these studies are based on water or ethylene glycol. Journal of nanofluids american scinetific publishers. Proceedings of the asme 2016 heat transfer summer conference collocated with the asme 2016 fluids engineering division summer meeting and the asme 2016 14th international conference on nanochannels, microchannels, and minichannels. Nanolayer and nanoconvection based enhanced thermal conductivity of copperco 2 nanofluid. Nanofluid is an advanced kind of fluid, which contain nanometer sized 109 m solid particles known as nanoparticles. Split system refrigerant piping guide r410a refrigerant subject to change without notice.
Hu, influences of refrigerant based nanofluid composition and heating condition on the migration of nanoparticles during pool boiling. Energyeconomic analysis of plate evaporator using brinebased hybrid nanofluids as secondary refrigerant a bhattad, j sarkar, p ghosh international journal of airconditioning and refrigeration 26 01, 1850003, 2018. Performance analysis of a refrigeration system using nano fluid. In this paper the migration properties of nanoparticles during pool boiling of a nanorefrigerant have. Apr 19, 2019 an extensive experimental investigation on the thermophysical properties of two different types of r718 water based nanofluid was performed for particle volume fractions. Experimental analysis of a refrigeration system using al2o3. Controlling a multievaporator refrigeration system that. Nanofluid technology is a relatively new field, and as such, the supporting studies are not extensive. Performance analysis of a refrigeration system using nano. Procedia engineering 56 20 310 315 p rp t r t 2 1, 1 1. During the nanofluid mql grinding, a dense and hard slurry layer was formed on the wheel surface and could benefit the grinding performance. Micro gas chromatography, refrigerant analysis, product quality abstract the importance of refrigerant composition analysis became clear when contaminated and counterfeit refrigerant 1,1,1,2tetrafluorethane r4a appeared on the market.
Applications of nanofluids in condensing and evaporating. Refrigerant based nanofluid is a new type of heat transfer working fluid by dispersing nanoparticles in conventional pure refrigerant, and is also called as nanorefrigerant by some researchers ding et al. The objective of this paper is to experimentally investigate the influences of cnts physical dimension, refrigerant type, oil concentration, heat flux, and initial liquidlevel height on the migration characteristics of cnts in the refrigerantbased nanofluid pool boiling at different original cnts concentrations, and to propose a model for. Therefore, the condition of nanoparticles during this phase change needs to be clarified. In this paper, experimental analysis is examined to estimate hydrothermal behavior of refrigerantbased nanofluid nanorefrigerant during condensation inside a horizontal tube.
To apply the nanofluids to actual systems, it is necessary to. A nanofluid is a fluid containing nanometersized particles, called nanoparticles. They believed that the nanolayer provides an effective. Nanofluids can be utilized as efficient heat transfer fluids in many thermal energy systems to improve the systems thermal efficiency. Thermal conductivity, viscosity and density of r141b refrigerant. This study is about the performance evaluation of a shell and tube heat exchanger operated with nanofluid.
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