Nano Lubricant Research Articles

Primena analize konačnih elemenata kod radijalnog ležaja podmazivanog nano mazivima

The oil-film pressure is a key factor used to examine the performance of a journal bearing. The developed nano lubricant was used as an alternate lubricant for journal bearing system described in the present study. For this purpose, oil-film pressure of the journal bearing was analyzed by using COMSOL multi physics and developed the oil-film pressure of the journal bearing lubricated with various lubricants. The COMSOL results stated that, this model is suitable for analyzing the pressure of an oil-film of the journal bearing and these results were compared with experimental results.

Review on The Energy and Exergy Analysis of Vapour Compression Refrigeration System Using Nanolubricant

The vapour compression refrigeration system (VCRS) is an energy system used for preservation and cooling of household, agricultural and industrial products but the energy consumption of the system is high globally. With this challenge, the need to reduce the energy consumed and enhance its performance becomes eminent. The thermal conductivity of heat transfer fluids plays a significant role in the heat transfer characteristics of the fluid and the overall performance of an energy system. The low thermal conductivity of refrigerant can be enhanced by dispersing nanoparticles into the refrigerant. The use of nano refrigerant or nano lubricant has been found to be useful in the reduction of energy consumption and enhancement of the VCRS performance. This review discusses the energy and exergy performance of the VCRS with the aim of identifying some critical factors that affects the performance optimization and exergy destruction within the system.

Experimental investigation of turning Al 7075 using Al2O3 nano-cutting fluid: ANOVA and TOPSIS approach

The evolution of modern industry tends to use aluminium based alloys due to its low density and high hardness. While machining aluminium, one of the major failure modes of cutting tool is the material being machined adheres to the tool cutting edge. This leads to poor surface quality characteristics. Tough different tool materials and tool coatings are available, achieving better machining parameter is still under research. Hence, in this work, Al 7075 is machined using CNC lathe under dry and with the nano lubricant of Al2O3 of 5%. The turning experiments were carried out in Siemens—CNC lathe to investigate the best operating conditions. There are 27 experiments based on full factorial approach is performed. The machining parameters are speed, feed and depth of cut. The output parameters are metal removal rate (MRR) and surface roughness (SR). The regression models developed from ANOVA are significant. To find best operating parameter TOPSIS is performed under each machining conditions. From the test results, it is concluded that the 1% of Al2O3 nano lubrication gives better value of both MRR and SR.

Role of base oils in developing extreme pressure lubricants by exploring nano-PTFE particles

Abstract The suitability of various basestock oils based on classification by American Petroleum Institute (API) as Group I, II, III and IV with polytetrafluoroethylene (PTFE) nano-particles (NPs) as extreme-pressure additive (EPA) in oil was investigated. The nano-lubricants (NLs) with 3% NPs of PTFE (≈230 nm) were evaluated for their physical and tribological performance along with an in-depth studies on the stability aspects. The worn surfaces were examined thoroughly to analyse the mechanisms. Group I based NL, showed the highest weld load (620 kg) with 288% improvement. This was attributed to synergistic chemical action of PTFE NPs and Sulphur (in the base oil) with the base metal surface to form a stable and robust tribo-film.

Experimental investigation of two phase flow boiling heat transfer of mixtures of refrigerant R410A and nanolubricants in a horizontal smooth copper tube

In air conditioning systems, a small amount of lubricant leaves the compressor and circulates through the system. The lubricant acts as a contaminant, affecting heat transfer and pressure losses in heat exchangers. The mixture of refrigerant and nanolubricants (NLs), that is, nanoparticles dispersed in the lubricant oil, have shown potential to augment the two-phase flow boiling heat transfer in the literature. However, the mechanisms of heat transfer enhancements due to the NLs are still not well understood. Published models of two-phase flow boiling lack experimental validation with refrigerant and NL mixture. This work addresses this gap by presenting new experimental heat transfer coefficient and pressure drop results for the saturated two-phase flow boiling of R410A with two NLs in a 9.5 mm I.D. smooth copper tube: a ZnO nanoparticle laden lubricant and a γ-Al2O3 nanoparticle laden lubricant. In smooth tube, R410A–NL mixtures, which had higher thermal conductivity and kinematic viscosity than R410A–POE lubricant mixture, showed degradation in heat transfer coefficient compared to R410A–POE lubricant case; but they also had lower pressure drops. Relocation of the nanoparticles closer to the inner wall of the tube could lead to enhancement in heat transfer at an expense of increased frictional pressure drop.

Effects of Nano-Lubricants on Power and CO Emission of a Diesel Engine: An Experimental Investigation

In this study, it was aimed to investigate the effects of copper (II) oxide (CuO), copper zinc iron oxide (CuZnFe2O4) and copper iron oxide (CuFe2O4) nanoparticle additives in synthetic diesel engine oil (5W-40) at the fraction of 0.08 wt% on friction and wear in piston ring-cylinder liner mechanism of the engine. In this regard, Scanning Electron Microscope (SEM) analyses of the nanoparticles were first carried out and via a linear reciprocating tribometer, friction coefficients were determined on specimens comprised of the same material with real engine piston ring. Subsequently, SEM analyses of the samples exposed to abrasion were carried out to investigate the wear characteristics. In the second stage of the experimental study, oil sump of the diesel test engine was filled with raw oil (oil without nano additives) and prepared nano oils (oil+nano additives) separately to unravel the effects of the lubricants on engine power and carbon monoxide (CO) emissions. According to the results, it was determined that CuZnFe2O4 nano lubricant was the most pronounced of all in terms of tribological performance, engine power and CO emissions. The results depicted that, in the best case, an average increment of 15% in engine power and an average reduction of 18% in CO emissions with CuZnFe2O4 nano oil were provided compared to that of the raw oil.

Effect of Addition of Different Mass Fractions of CuO Nano Particles in Compressor oil upon COP of the Refrigeration System

Nano fluids are produced by mixing particles of nano dimensions in the standard fluids. Thermal conductivities of the nanofluids are higher than that of the base fluids. These are the properties which makes nanofluids unique and superior to normal solid liquid suspensions. i) heat transfer between the particles and fluid is higher due to the high surface area of the particles ii) enhanced dispersion stability with pre-eminent Brownian motion iii) particle clogging is minimized iv) Power required for pumping is less as compared to the base fluid for proportionate heat transfer. In this project Cu0 nanoparticles of size 20nm-50nm has been used as Nano lubricant for performance study of Refrigeration test rig. CuO nanoparticles are mixed in POE oil (Compressor oil) to form the nanolubricant. The nanolubricant so formed is further stabilized by Ultrasonic agitation. Nano lubricants with specific mass fractions 0.30%, 0.70%, 1.05%, 1.4% are added in the compressor oil and the experimentation is carried out which shows significant improvement in the performance of refrigeration system. Compressor work is reduced and consequently COP of refrigeration system is improved.

Assessing the Performance of Nano Lubricant on Zinc Aluminium Alloy

In the field of tribology, Zinc Aluminium (ZA) alloys have been widely investigated for their superior wear characteristics. They were found to be suitable alternatives for bearing bronzes for the operating conditions of high mechanical load and moderate sliding speeds. Addition of nano-particles in the lubricating oil (base oil) to enhance the characteristics of the base oil is known as nano lubrication. In this study, sliding wear behaviour of ZA27 was investigated under dry, base oil and nano oil lubrication conditions, by varying load, sliding distance and sliding speed. With the base oil as SAE 40, nano graphite was added in two step method which was further used to identify the lubrication regime under different lubrication conditions. From the limited study of single melt samples, the results appear that the wear behaviour of ZA27 alloy improved under nano lubrication conditions with reduction in operating temperature. It could be observed from SEM images that the presence of nano-particles reduced scarring and wear, leading to enhancement in the tribological performance of ZA27 alloy.

Performance Study of Ducted Air-Conditioning System with Different Mass Fraction of Al2O3Nanofluids

The coefficient of performance (COP) of VCR system is depends on the refrigeration effect and work required. It is increased by increasing the rate of heat transfer or by reducing the compressor work. Recently it is found that the use of nanotechnology in the refrigeration system can increase the performance of system. This research is on the concept, application, properties of the nanofluids & experimentation on ducted air conditioning system by using various mass fractions (0.25%, 0.50%, 0.75%, and 1.00 %.) of Al2O3 nanoparticles. In this experiment the nanoparticles are added into the base fluid which is lubricating oil (POE oil) of Compressor. It has been found that Nano lubricant has much higher temperature dependent thermal conductivity than conventional lubrication oil and it improves the thermo-physical properties. This can be considered as one of the key parameter of enhanced performance for refrigeration & air conditioning system. This research is performed in order to check and clarify the effect of Nano lubricant on the air conditioning system.

Influence of Adding CuO and MoS2 Nano-particles to Castor Oil and Moulding Oil on Tribological Properties

The tribological properties of adding copper oxide (CuO) and molybdenum disulfide (MoS2) nanoparticles powder in both organic (castor oil) and mineral oil (moulding oil) were investigated. These properties include coefficient of friction and wear between two surfaces, CK50 steel alloy and 2024-T4 aluminum alloy. The Nano lubricants were prepared by dispersing CuO and MoS2 nanoparticle powders at variable weight fractions 0.3, 0.5, 0.7, 1.0 and 2.0% in each oil lubricant. The friction and wear tests were carried out using a pin on the disk test principle by the vertical universal friction testing machine (MMW-1A). The instability problem with the lubricant suspension was solved by adding different weight fractions of GUM ARABIC, which leads to 2% of it gives more stable suspensions. The best results from both friction and wear Tribo tests are observed in 1%W of adding both nanoparticles to both oil lubricants. The formation of Tribo film due to the adsorption and adherence of Nano additives on the surfaces was responsible in reducing the wear properties. Hybrid (1%Wt CuO + 1Wt% MoS2) nanoparticles that added to both oils indicates more decreasing in friction and wear compared to the base oil. The coefficient of friction for hybrid Nano-particulate lubricants reduced to 81.7% and 76.03%, while the wear rate reduced to 93.17% and 92.23% compared to castor oil and moulding oil respectively as a base oil. The study provides insights into how Nano-lubricant additives could contribute towards tribological enhancement and improved product quality.

Development and testing of nano particulate lubricant for worm gear application

Bio-degradable lubricants are an attractive alternative for the mineral based and synthetic based lubricants. Bio-degradable lubricants are environmental-friendly and non-toxic. The present study deals with the tribological investigation of bio-degradable nano lubricants for worm gear applications. Nano additives like CuO and TiO2 were used. Bio-degradable oils like palm oil and sunflower oil were used as base oils. The nano lubricants were prepared by adding two nano additives and two bio-degradable oils each of 0.1 % and 0.2 % weight composition. Friction and wear characteristics were tested on pin-on-disc tribometer under varying load conditions. Extreme pressure tests for nano lubricants were carried out using four ball tester. The wear surface obtained was analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy. From the tests conducted, it was found that the addition of nano additives in biodegradable oils reduced the friction co-efficient and wear rate to a considerable extent.

Surface-capped copper nanoadditive for improvement of base oil properties

Copper nanoparticles surface-capped by alkanethiol with long carbon chain length was prepared successfully by chemical reduction method. 1-dodecanethiol was used as the coating material for the desired smooth and protected surface. Various reaction parameters, like effect of pH, molar ratio of the reactants etc. had been tested experimentally to explore the most suitable and economical way of using the chemical reduction method. Uniform, smooth surface and spherical shaped copper nanoparticles, with particle size of about 40-60 nm had been produced successfully. Copper nanoparticles surface-capped by alkanethiol (C12S-Cu) was characterized by means of x-ray diffraction, scanning electron microscopy, Fourier transform infrared spectrometry and ultraviolet-visible spectroscopy. Uniform dispersion of copper nanoadditive in base oil using ultrasonic method was investigated. The tribological behavior of C12S-Cu as an additive for base oil was evaluated. Viscosity, pour point, and flash point of nano lubricants at different concentrations of nanoadditive (0.2, and 0.5 wt %) were evaluated.
 Bangladesh J. Sci. Ind. Res.54(1), 1-10, 2019

EFFECT OF LUBRICANT TEMPERATURE ON THE DYNAMIC AND STABILITY BEHAVIOR OF NANO-LUBRICATED JOURNAL BEARING

The effects of lubricant temperature on the dynamic behaviour of Nano-lubricated finite length journal bearings has been investigated in the present work. Modified time dependent Reynolds equation include the effect of oil film temperature was perturbed in order to calculate the eight dynamic coefficients (four stiffness, and four damping) required to evaluate the dynamic characteristics of the journal bearing, the oil film temperature was obtained by solving numerically the energy and heat conduction equations simultaneously with the Reynolds equation using appropriate boundary conditions. Suitable viscosity temperature model has been used to consider the effect of oil film temperature. The bearing lubricated with oil containing Titanium dioxide (TiO2 ) nanoparticles dispersed in to the base oil with various particle concentration. The effect of adding TiO2 Nano-particles with various particle concentrations (0.1%, 0.5%, 1%, 1.5% and 2%) in order to enhance its viscosity has been discussed. A validation to the mathematical model and the computer program written in Fortran90 prepared to solving the governing equation has been carried out by comparing the result for the dynamic coefficients (stiffness and damping) obtained in the present work with that obtained by Sheeja and Prabhu . The results seen to be in a good agreement with percentage of error less than 2%. The results obtained in the present study show that the bearing stiffness coefficients increases by 30% while the damping coefficients increased by 27% when the bearing lubricated with Nano lubricant that contains TiO2 Nano particles with particle concentration of (1.5%).

Superlow friction and diffusion behaviors of a steel-related system in the presence of nano lubricant additive in PFPE oil

The lubrication performances of diamond like carbon (DLC) films were investigated by a ball-on-disc tribometer under perfluoropolyether (PFPE) oil lubrications. The influence of nano lubricant additives in PFPE oil on the tribological properties of DLC films was evaluated. The experimental results show that the solid-liquid synergy lubrication is beneficial to improve the tribological properties of the steel-related friction system and the tribological properties of the friction pair are significantly influenced by lubrication modes and the types and contents of nano lubricant additives under PFPE oil lubrication. The friction system exhibits super low friction behaviors under PFPE oil with nano MoS2 lubricant additive lubrication due to the excellent compatibility of nano MoS2 additives with PFPE oil. Coefficient of friction (CoF) of the friction system is as super low as 0.02 under PFPE oil with 0.2 wt.% nano MoS2 additive lubrication. Superlow friction mechanism is attributed to the pointlike contact of nano MoS2 additive as soft phase and the excellent diffusion behaviors of nano MoS2 additives in PFPE oil. The potential usefulness of nano MoS2 particles as the lubricant additives in PFPE oil for the steel/DLC films has been demonstrated.

Characteristical Study of Coconut Oil Based Nano Lubricant

Use of mineral oils as lubricants did created concerns because of the environmental issues. Use of mineral oils as lubricating oil in machineries create pollution problem. Sometimes the pollutions formed as a result of use of mineral oil may be hazardous to the environment, to the livings including humans. Vegetable oils are widely considered as a replacement for the existing conventional oils because of the renewable and biodegradable properties. They show good lubrication properties. Coconut oil is a vegetable oil which shows greater lubrication properties. Low oxidation and thermal stability, weak low-temperature properties and narrow range of available viscosities are the main disadvantages of coconut oil as lubricating oil. Butylated hydroxyl toluene as antioxidants, Ethyl Cellulose as pour point depressants and CuO nanoparticles were added to the coconut oil and physical, chemical and tribological properties were studied. From those analyses, the optimum concentrations of antioxidants, pour point depressants and nanoparticles obtained are 2%wt, 3%wt and 0.5%wt respectively. By adding optimum concentrations of additives and nanoparticles, coconut oil based nanolubricant was formulated.

Experimental Investigation to Enhance the Performance of High Speed Reduction Gearbox using Nano Blended Lubricants

The sliding motion between worm and worm wheel is the inherent factor that makes the worm and worm wheel drives less efficient among all the gear drives. Efficiency of these gears varies between 40 to 90%. They need good lubricants, which has high heat dissipation capacity and low coefficient of friction for improving the efficiency. The lubricants considered in the current investigation play a significant role in decreasing the power losses in gearbox besides the geometry of the gears. Nano blended lubricants are found to have efficient tribological and thermal physical properties such as, less frictional coefficient and high heat transfer coefficient. Al2O3 Nano particles of 30 nm size dispersed in SAE 140 mineral oil at different volume fractions resulted decrease in frictional coefficient and found varying from 0.1 to 0.5% nano particle volume fractions. Further, heat transfer coefficient is enhanced by 46.35% for volume fraction of 0.5% and also temperature rise of nano blended lubricant was found to be less than that of base lubricant. The overall efficiency of the selected gearbox with which the experimentation has been done was found to be increased with usage of nano blended lubricant. The performance of the gearbox using nano lubricant at 0.5 volume percent is found improved by 4.85 and 7.86% at operating temperatures 35 and 60oC, respectively compared to the performance of the gearbox using base lubricant.

An experimental study on characterization and properties of nano lubricant containing Cellulose Nanocrystal (CNC)

Nano-lubricant is a new kind of engineering lubricant composed of nanometer-sized particle dispersed in a base lubricant. Recently, nanoparticles have been explored as lubricant additives for improving the stability and lubricity properties of a technological fluid. Cellulose nanocrystals (CNC), a unique and natural material extracted from native cellulose, has gained much attention in many field application due to its remarkable physical properties, special surface chemistry, and excellent biological properties, making them attractive as a green lubricant additive. The purpose of this study is to investigate the characterization of the CNC nanoparticles and to evaluate the influence of CNC nanoparticles on the lubricating properties added to the base oil. In this study, CNC nanoparticles were prepared and suspended in five different volume concentrations in the engine oil (0.1, 0.3, 0.5, 0.7 and 0.9%). The kinematic viscosity and viscosity index of the resulting nano lubricant was determined while varying both the nanoparticle volume fraction and the temperature. The size, morphology, and structure of CNC nanoparticles were characterized using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX) and X-ray diffractions (XRD). The dispersion analysis of CNC nanoparticles in lubricating oil using UV spectrometer confirms that CNC nanoparticles possess good stability and solubility in the lubricant and improve the lubricating properties of the engine oil. The overall results of this experiment reveal that the addition of CNC nanoparticle with base 0il SAE40 lubricant shows the highest value of VI and most suitable concentration for improving properties of the base oil.

Experimental Study: The Effects of Using Nano-Lubrication on the Performance of Refrigeration Systems

An experimental apparatus was built to investigate the performance of a refrigeration system based on the coefficient of performance (COP) and energy consumption of an air conditioning device. Enhancement of performance of a window unit air conditioning device was sought by mixing nanoparticles with mineral oil (MO 4E) to act as a lubricant, using R22 refrigerant as a working fluid. Different concentrations of Al2O3/Mineral Oil (MO 4E) were mixed by using ultrasonic and other mixing devices. The results showed that the COP was increased and energy consumption decreased when nano lubricant was used, and that the optimum concentration was 0.05% Al2O3 by mass, where the enhancement in COP was 25% compared to plain MO 4E; the energy consumption in the compressor was also lower. Thus, enhancing the coefficient of performance (COP) of the system by adding a small percentage of nanoparticles to the lubricant oil appears to be feasible.

Thermophysical properties of polyalphaolefin oil modified with nanoadditives

This article presents an experimental investigation on the effects of concentration and morphology of nanoadditives on the thermophysical properties of nanolubricants (NLs) at different temperatures. A polyalphaolefin (PAO6) oil was used as base fluid. A two-step method was used to prepare the NLs. Zirconium oxide (ZrO2) and boron nitride (BN) nanoparticles (NPs) and graphene nanoplatelets (GnP) were separately dispersed in the base fluid with mole fraction ranging from 0.05 wt% to 2 wt%. The NPs and GnP were characterized by X-ray diffraction, Raman spectroscopy and electron microscopy. The base oil was also analysed by mass spectrometry. Visual sedimentation, temporal variation of refractive index and Fourier transform infrared spectroscopy were used to analyze the stability of the nanolubricants and the existence of new interactions between nanoparticles and base oils. Detailed study was carried out to analyse the effect of nanoadditives on viscosity, density and adiabatic bulk modulus. Moreover, different predictive equations to estimate termophysical properties were tested using the experimental values. Pressure-viscosity coefficients as a function of the temperature and nanoparticle concentration were predicted for all the nanolubricants.

Enhancing the Performance of Vapour Compression Refrigeration System using Nano Refrigerants: A review

Application of Nano particles as additives in refrigerants has been identified as a way of enhancing the performance of the vapour compression refrigeration system (VCRS) without modifying the system components. When Nano particles are dispersed in a refrigerant or lubricant, they are regarded as Nano refrigerants or lubricants. The improvement in heat transfer and tribology are responsible for the enhancement of VCRS performance. In this review paper, the effect of Nano particles on the coefficient of performance, power consumption, thermal conductivity, viscosity and heat transfer of refrigerants are discussed. It is shown that the application of Nano particles as additives in refrigerant and lubricant in VCRS is favourable and promising. Therefore, Nano refrigerants are expected to be the future refrigerants to be adopted by VCRS manufacturers.