Nanofluid Research Articles

Low-salinity water flooding by a novel hybrid of nano γ-Al2O3/SiO2 modified with a green surfactant for enhanced oil recovery

This paper introduces a hybrid enhanced oil recovery (HEOR) method that combines a low-salinity water flooding (LSWF) and nanoparticles (NPs) stabilized with a green surfactant. We experimentally investigated the use of combinations of silica (SiO2) and gamma alumina (γ-Al2O3) nanohybrids stabilized with Gum Arabic (GA) at different water salinities. Nanofluids (NFs) were prepared by dispersing γ-Al2O3 and SiO2 NPs (0.1 wt%) in deionized water (DW), synthetic seawater (SSW), 2, 5, and 10 times diluted samples of synthetic seawater (in short 2-DSSW, 5-DSSW and 10-DSSW, respectively). The challenge is that NPs become unstable in the presence of cations in saline water. Moreover, an attempt was made to introduce NFs with high stability for a long period of time as the optimal NFs. The effects of temperature on the behaviour of optimal NFs in the presence of different base fluids, distinct mass ratios of γ-Al2O3/SiO2 and various concentrations of surfactant were analysed via interfacial tension (IFT) and viscosity measurements. The results of the viscosity measurement showed that with increasing temperature, the NPs dispersed in DW had lower viscosity than NPs dispersed in various salinities. However, the IFT measurement for NPs dispersed in different base-fluids revealed that with increasing temperature and presence of cations in saline water, IFT values decreases. Although, the minimum IFT for hybrid nanofluid (HNF) γ-Al2O3/SiO2 modified with GA and dispersed in 10-DSSW was reported 0.99 mN/m. Finally, according to the micromodel flooding results, in oil-wet conditions, the highest oil recovery for combination γ-Al2O3/SiO2 modified with GA and dispersed in 2-DSSW was reported 60.34%. It was concluded that NFs modified with GA could enhanced applicability of LSWF via delay in breakthrough time and improving sweep efficiency.

Aspects of double slip on multiphase inclined channel flow of Casson and Cu-nanofluid

The key aspect of this study is to inspect the entropy generation (EG) of heat and momentum transport within two immiscible Casson and nanofluid (NF) with mass diffusion of copper nanomaterials in an inclined channel (IC) with thermal and velocity slips. The IC is divided into two regions. Region-I contains the Casson fluid (CF) whereas Region II is occupied with copper-water NF. Moreover, the effects of Lorentz force are also taken in region II having copper-water NF. The mathematical model is solved by employing the perturbation method. The behavior of different aspects, i.e., mass diffusion of copper nanomaterials, Lorentz force, velocity and thermal slips on EG, and transport of mass and heat are presented in graphs and tabular forms. Furthermore, the numerical outcomes of friction at the walls and the rate of heat transport are presented in tabular form. Our results show that the EG and the rate of EG decline when the dispersion of nanomaterials is increased. The velocity and temperature decline when Lorentz force is increased in Region II. Furthermore, temperature augments with the rise in CF parameter and thermal slip parameters whereas velocity also increases with the rise in velocity slip parameters. So, the thermal performance can be enhanced in an IC by using blood fluid in one phase and thermal slips at the walls.

Melting heat transfer of a quadratic stratified Jeffrey nanofluid flow with inclined magnetic field and thermophoresis

Recently, researchers are facing great challenges to form the homogeneous solutions of various liquids at biomedical and industrial levels. Such homogeneous solutions can be controlled through stratification phenomenon directly which is ignored by the researchers in the existing literature specifically quadratic stratification and melting heat mechanism which is valid only for higher temperature processes. Thus, to form the homogeneous and stable liquid solutions for various industrial processes, we investigate the melting heat phenomenon in quadratic stratified Jeffery Nano fluid flow deformed due to linearly stretching sheet along with stagnation point. Inclined constant magnetic field is implemented on the fluid through an arbitrary angel. Characteristics of heat and transportations are disclosed through viscous dissipation, Brownian motion and thermphoresis. Temperature and concentration of the surrounding fluids are assumed higher than the stretching surface. The resultant governing equations are reduced to ordinary differential equations through proper transformations. Convergent analytical series solutions are computed via homotopic approach. Impact of various emerging parameters on temperature, velocity and concentration fields are illustrated and discussed comprehensively. Sherwood and Nusselt numbers and drag force are scrutinized mathematically, physically and graphically. It is analyzed from the study that (i) dominant melting reduces the temperature field (ii) higher thermal and solutal stratification decay the temperature and concentration fields respectively (iii) higher thermophoresis enhances the temperature field. Further, it is concluded that stable and homogeneous solutions may be made by increasing melting and reducing stratification phenomena. This study will help us to provide actual amount of heat for heating processes in industries and biomedicine which is the basic requirement for excellent quality of products.

Analytical investigation of heat and mass transfer in MHD nano fluid flow past a moving vertical plate

This study aims to derive analytical expressions for temperature, concentration, and velocity in an unsteady MHD convective nanofluid flow past a moving vertical plate. The governing nonlinear differential equations are solved analytically using the Homotopy Analysis Method (HAM). The resulting solutions are presented as concentration, temperature, and velocity profiles, allowing for the analysis of various physical parameters' influence on the flow behavior. Furthermore, our analytical results are validated by comparing them with existing numerical solutions using MATLAB. The impact of these parameters on skin friction, the Nusselt number, and the Sherwood number is presented, demonstrating good agreement with previously reported data. The findings of this research hold significance for industries involving heat transfer processes, such as thermal management systems, electronic cooling, and energy generation applications.

Thermal and surface properties of AlZnO and surfactant-stabilized AlZnO nanofluids: Influence of sonication duration for heat transfer applications

Research into doped metal oxide nanofluids (NFs) has intensified due to recent breakthroughs in heat transfer applications. This study explores the thermophysical properties of Aluminum Zinc Oxide (AlZnO) at a 0.10 vol% concentration and surfactant-enhanced Aluminum Zinc Oxide (f@AlZnO) at concentrations of 0.05, 0.10, and 0.20 vol%. Experiments were conducted across a temperature range from 20 to 80°C. The study utilized various analytical techniques such as FT-IR, UV–visible spectroscopy, Powder XRD, SEM, and EDX to examine the effects of volume concentration and sonication duration on stability, particle size, thermophysical properties, contact angle, wettability, and surface tension. It was found that the thermal conductivity of AlZnO and f@AlZnO NFs increases with both volumetric concentration and temperature. Notably, surfactant inclusion significantly enhanced the stability of AlZnO NFs, achieving a high zeta potential after 160 minutes of sonication. The 0.10 vol% f@AlZnO NF displayed optimal stability at this sonication duration, while the 0.10 vol% AlZnO NF showed the smallest particle size distribution after just 20 minutes. Thermal conductivity enhancements of 5 %, 2.5 %, 2 %, and 1.9 % were observed for 0.10 vol% AlZnO NF and 0.05, 0.10, and 0.20 vol% f@AlZnO NFs, respectively. Additionally, at 200 minutes of sonication, the 0.05 vol% f@AlZnO NF demonstrated the lowest increase in specific heat capacity. The study also revealed that both surfactant addition and increasing volumetric concentration of AlZnO NFs reduced surface stress and contact angle values. In contrast, dynamic viscosity and density increased with higher nanoparticle concentration and decreased with rising temperature. The Mouromtseff number calculations underscore the potential of AlZnO NFs in thermal applications, meriting further investigation. This comprehensive examination provides critical insights into the effective utilization of hybrid metal oxide NFs in heat transfer applications.

Performance Analysis of Double Pipe Heat Exchanger Using Nano Fluids

Performance Analysis of Double Pipe Heat Exchanger Using Nano Fluids

Comparative study of thermal performance improvement of parabolic trough solar collector using different heat transfer fluids, economic and environmental analysis of power generation

The use of nanofluids (NFs) as heat transfer fluids (HTFs) is one way of improving the thermal performance of parabolic trough solar collectors (PTSCs). This study presents a comparative analysis of the thermal performance of a PTSC using nanofluids as HTF. Two categories of nanoparticles (NPs) (green and conventional) and two base fluids (water and Syltherm 800) giving eight nanofluids are used in a one-dimensional quasi-static thermal model, simulated from a numerical code written in Matlab. After numerical validation of the proposed model, the comparative analysis in static and dynamic regimes linked to solar radiation shows that green NPs present not only differentiated positive but also negative effects on thermal performance depending on the base fluids compared to conventional NPs, and that the combination of green nanoparticles with high thermal capacity base fluids presents more positive than negative thermal effects. The impact of conventional NPs is more significant with water, at around 0.005 MWh, than with Syltherm 800, which averages around 0.002 MWh. The use of HTF configurations based on Syltherm 800 increases production by around 1 MWh more than that of water. HTF configurations based on Syltherm 800 generate around $0.004/kWh less than water on average. HTFs based on Syltherm 800 produce around 7.5 kgCO2/year more than water.

ZrC–Au core-shell nanoparticles for efficient solar photothermal conversion

Nanoparticles (NPs) have attracted much attention recently because of their excellent photothermal properties. In particular, nanofluids (NFs) based on core-shell plasmon NPs have become the key to solar thermal utilization. This work proposed an ZrC–Au core-shell NP suitable for direct absorption solar collectors (DASCs). The optical properties of ZrC–Au core-shell NP are investigated based on the finite element method (FEM). The physical mechanism of its existence can be explained by the surface plasmon resonance and localized surface plasmon resonance of ZrC–Au core-shell NP. Meanwhile, the effect of core-shell size on the NP optical properties of ZrC–Au core-shell is investigated based on electromagnetic field distribution. In addition, the effects of length (H) and mass flow (ṁ) on the temperature rise and efficiency of the collector (η) are analyzed with DASC 2D simulation. Research shows that ZrC–Au core-shell NPs with t = 5 nm and r3 = 15 nm can effectively broaden the solar spectral absorption band, increase the absorption peak value, and the photothermal conversion efficiency (fv = 20 ppm, h = 15 mm) reaches 96 %, which is 15.89 % higher than Au NP. Meanwhile, the η of ZrC–Au NPs can be improved by ∼8.86 % compared with Au NPs under specific parameters (H = 2 cm, L = 20 cm, fv = 20 ppm, ṁ = 1 g/(s m)). Combined with the preparation possibility and economy of ZrC–Au core-shell NPs, the broad application prospect of this NP in DASC and other photothermal fields was analyzed.

Examination of smart battery thermal management system using the counter flow of air and nanofluid for cooling cylindrical rechargeable batteries for better resilience

This paper examines smart thermal management of a battery pack (BTK) with a square arrangement of 16 cylindrical battery cells numerically. The cooling of the battery is carried out simultaneously using laminar airflow in a channel and laminar nanofluids (NFs) flow in the tube inserted between the battery cells. The BTK includes rechargeable lithium-ion cells and a tube placed in the channel. The inlets of air and NFs are counter-flow, and the study is done at constant air velocity for different NFs velocities in the tube from 0.001 to 0.003 m/s and different volume percentages (VOP) of NFs from 1 % to 3 %. The numerical study is performed transiently using the finite element method in 2000 s. The results demonstrate that the use of NFs and air for the thermal management (THMT) of battery cells results in better temperature uniformity on the battery cells, especially in the rows placed at the outlet. An increment iimproveP of nanoparticles improves the heat transfer coefficient (HTRC) between air and NFs flows. Also, enhancing the VOP of NFs increases the temperature of the outlet air and decreases the temperature of the outlet NFs. The average temperature (T-Av) and the maximum temperature (T-Mx) of the BTK are high until the battery is charged. They are reduced when the battery charge is stopped due to the air and NFs flows.

Superwetting Nanofluids of NiOx-Nanocrystals/CsBr Solution for Fabricating Quality NiOx-CsPbBr3 Gradient Hybrid Film in Carbon-Based Perovskite Solar Cells.

The wettability of precursor solution on substrates is the critical factor for fabricating quality film. In this work, superwetting nanofluids (NFs) of non-stoichiometric nickel oxide (NiOx) nanocrystals (NCs)-CsBr solution are first utilized to fabricate quality NiOx-CsPbBr3 hybrid film with gradient-distributed NiOx NCs in the upper part for constructing hole transport ladder in carbon-based perovskite solar cells (C-PSCs). As anticipated, the crystalline properties (improved crystalline grain diameters and reduced impurity phase) and hole extraction/transport of the NiOx-CsPbBr3 hybrid film are improved after incorporating NiOx NCs into CsPbBr3. This originates from the superb wettability of NiOx-CsBr NFs on substrates and the excellent hole-transport properties of NiOx. Consequently, the C-PSCs with the structure of FTO/SnO2/NiOx-CsPbBr3/C displays a power conversion efficiency of 10.07%, resulting in a 23.6% improvement as compared with the pristine CsPbBr3 cell. This work opens up a promising strategy to improve the absorber layer in PSCs by incorporating NCs into perovskite layers through the use of the superwettability of NFs and by composition gradient engineering.

Next-Gen Lubrication: Water-cooled thrust bearings in conjunction with nano fluid lubricant

Thrust bearing finds application as a key element for heavy duty machines such as hydro-power plants (vertical shaft), submarines, steam engines, cement plant-ball mills (horizontal shaft) etc. Bearing temperature is a primary factor that affects the performance of hydrodynamic thrust bearings. Thermal deformation, misalignment, reduction in minimum oil film thickness and subsequent drop in load carrying capacity, are some of the manifestations related to high bearing temperatures. The present study attempts to decrease the bearing temperature by utilizing novel hybrid bearing set up. It involves the integration of water-cooled pads coupled with nanoparticle-infused lubricant films. This approach represents a convergence of two key technologies aimed at addressing the thermal effects linked with elevated temperatures generated during the operation of bearings. This study utilizes computational simulations to evaluate the effect of integrated thrust pad design on performance characteristics like pressure, temperature, and thermal deformation of a thrust bearing. The simulation results of new integrated design confirm (i) enhancement in pressure values e.g. maximum pressure increases from 5.6 MPa to 6.5 MPa (ii) reduction of pad temperature values e.g. maximum pad temperature value reduces from 85℃ to 70℃ (iii) reduction of pad thermal deformation values e.g. maximum pad thermal deformation value reduces from 36.5 µm to 22.3 µm. By leveraging the direct cooling effect of embedded cooling circuitry and the enhanced thermophysical properties of nanoparticles, this novel configuration promises to unlock new levels of efficiency and reliability in thrust bearing operation.

Novel Approach to Augment Thermal Conductivity of Dihybrid Nanofluids

In this experimental study, the copper oxide (CuO) nano–particle (NP) was mixed with a water/ethylene glycol hybrid base fluid to form a hybrid nano–fluid (HNF). Further, this HNF was mixed with a MgO nano–particle and also separately with a TiO2 nano–particle to form two different dihybrid nano–fluids (DHNFs). For the preparation of nano–fluids, two-step procedure was used. In all three cases, the volume fraction of the NP was 0.25, 0.5, 0.75, 1.0, and 1.25%. The thermal conductivity (TC) of HNF was measured with KD2 pro and compared with the DHNFs' at temperatures 26, 28, 30, and 32°C. It was inferred that the CuO/TiO2 nano–particle addition in the water/ethylene glycol hybrid base fluid resulted in an average of 0.8% rise in thermal conductivity at chosen temperatures and volume fraction. Also, the agglomeration due to the presence of CuO/MgO was a critical issue at higher volume fractions such as 0.75, 1, and 1.25%. The MgO nano–particle addition in the CuO nano–particle also resulted in a 0.6% increase in thermal conductivity at 0.25 and 0.5% volume fraction. The result was that in the CuO/MgO - water-ethylene glycol nano–fluid combination the TC was enhanced by 29.57% compared with CuO/water/ethylene glycol at a volume fraction increase of 0.5%. Also, it was noted that the nano–particles volume fraction has little effect on thermal conductivity improvement at higher proportion.

Simulation of hybrid boiling nano fluid flow with convective boundary conditions through a porous stretching sheet through Levenberg Marquardt artificial neural networks approach

In the domain of artificial neural networks, the Levenberg-Marquardt technique stands out for its innovative approach and convergent stability. It generates a numerical approach for the progression of a hybrid Cu–Al2CO3/water nanofluid on a porous stretched sheet (HNF-PSS), employing regression plots, state transition measures, histogram representations, and mean squared errors. This work explores the analysis of the fluid flow problem associated with HNF-PSS, introducing a novel application of an intelligent computing system that utilizes the effectiveness of neural networks trained by the Levenberg-Marquardt algorithm (NN-TLMA). The initial mathematical expression, expressed in terms of partial differential equations (PDEs) for HNF-PSS, undergoes transformation into dimensionless nonlinear ordinary differential equations (ODEs). The collection of data for the envisioned NN-TLMA involves parameters influencing the velocity of the HNF-PSS system model, generated using the Lobatto IIIa formula. The efficacy of the suggested NN-TLMA for solving the HNF-PSS is robustly verified by examinations of state transition dynamics, regression analyses, mean square error, and error histogram studies. The consistent alignment of the obtained results with corresponding solutions attests to the legitimacy of the structure, achieving a high level of accuracy within the range of 10–6 to 10–8. Insightful findings demonstrate that the thermal Biot number contributes significantly to an upsurge in fluid temperature. Furthermore, an augmentation in nanofluid concentration and thermal profile is found to increase the porosity strength of the medium. Nevertheless, an attenuation in the velocity profile is noted under these conditions. The application of this simulation work can be found in optimizing the designs of heat exchanger, in biomedical application and in renewable energy processes.

Experimental investigation on the performance of MXene/C-dot hybrid nanofluid-based photovoltaic/thermal system: An Energy, Exergy, and Enviro-Economic analysis

Nanofluids (NFs) with exceptional heat transfer properties are increasingly being adopted in solar collectors as heat transfer fluid (HTF). Hybrid photovoltaic thermal systems are becoming more popular because they increase overall efficiency by producing both high- and low-grade electricity. This research focuses on the application of thermally efficient NFs for enhancing the thermal and electrical output of a photovoltaic/thermal (PV/T) system. Indoor experimental investigation was conducted on the PV/T system to find the thermally efficient HTF. Carbon quantum dot (C-dot), MXene and MXene/C-dot hybrid NFs were selected for experimentation. Thermo-economic factors (thermal conductivity, volumetric heat capacity, thermal property degradation rate, and cost) were used to optimise the NFs' concentration. Optimized C-dot, MXene, and hybrid NFs were used for experimentation in the PV/T system. Energy, exergy, and enviro-economic analysis was conducted on the PV/T system with each HTFs. The results show that the thermal efficiency of PV/T was enhanced by 5.39, 3.87, and 9.45 % with C-dot, MXene and hybrid NFs, respectively. Hottel-Whillier-Bliss (HWB) analysis was performed on the collector from the generated experimental data. The analysis states that at zero heat loss conditions, the thermal efficiency of the PV/T was enhanced by 5.4 % with the hybrid NF. The maximum CO2 emission from PV/T with C-dot, MXene, and hybrid NFs, were calculated to be around 2.024, 1.979, and 1.931 kgCO2/day, respectively. Emission cost reduction analysis states that the hybrid NF achieved the highest reduction of 0.02 $/day which was a considerable decrement of 13.5 % over the water-based PV/T system.

Influence of the twisting and nano fluids on performance of a triangular double tube heat exchanger

Abstract The hydraulic and thermals performance of flow in a double-tube heat exchanger with an inner twisted triangle tube of length L = 1 m has been studied numerically. Equations for energy, turbulence, and Navier–Stokes were used to model the fluid flow and heat transfer in a double-tube heat exchanger with an inner twisted triangle tube. The Reynolds number range was 5000–30,000 for nanofluid (water-Al2O3) as a working fluid under a turbulent flow regime. The considered configuration was examined by varying the volume concentration of nanofluid while keeping the twist ratio constant (Tr = 5). Different cases of volume concentration of nanofluid are triggered (0.05 %, 1 %, 2.5 %, and 4 %, respectively). The numerical outcomes of a double-twisted tube heat exchanger with an inner triangle-twisted tube are validated with the obtainable numerical data. The governing equations were solved with ANSYS Fluent 18.2. The findings reveal that the larger volume concentration of nanofluid (4 %) gives a greater Nusselt number and vice versa due to the increased thermal conductivity of the nanofluid in the double twist tube heat exchanger compared with a plain tube. However, the nanofluid Nusselt number grows with the rise of both the Reynolds number and volume concentration (Ø), and the best value of the Nusselt number is 210 when Reynolds number = 30,000 and Ø = 4 %. The effectiveness of the heat exchanger grows with an increase in the concentration of the nanofluid and a reduction in the torsion ratio compared to the normal tube. The effectiveness of the double-tube heat exchanger with an inner twist triangle tube increases to the highest value of 0.38 at Reynolds 30,000 and Ø = 4 %.

A Review on the Application of Nanofluids in Enhanced Oil Recovery

Abstract: Oil mobility has been a significant issue since the recovery of a heavy crude reservoir. It is determined by two factors: oil rheological properties and penetrability. Nanofluids (NFs) are a distinct class of engineered fluids characterized by the dispersion of nanoparticles ranging in size from 1 to 100 nanometers (nm) into a working fluid. They are divided into groups based on physicochemical characteristics, including nanoparticle morphology, and thermal and rheological properties. The well-known nanofluids composed of metal (e.g., ZrO2) and ceramic (e.g., SiO2) had the best physicochemical performance in terms of oil mobility. This chapter examines the inundation of metal and nonmetal based nanofluids as a new enhanced oil extraction (EOR) method for extracting primary and secondary oil from more than 45% of confined reservoir fluids. Furthermore, new developments in the utilization of these materials on EOR approaches to combat significant interfacial adhesion across sandstone and fluid interfaces are summarized.

Exploring the combined influence of primary and secondary vortex flows on heat transfer enhancement and friction factor in a dimpled configuration twisted tape with double pipe heat exchanger using SiO2 nano fluid

The double-pipe heat exchanger has a wider application in food industries, chemical industries, and a wide variety of fields where heat transmission is necessary. This investigation focuses on optimizing heat transfer rates through active, passive, and combined approaches. Within the realm of passive methods, this study specifically examines the use of twisted tape additions in pipe flow. In this study, different factors like swirl flow, primary and secondary vortex flows caused by tape twist, and the presence of a V-cut on the tape are studied. These factors include heat transfer rate, friction factor, and the standard for judging the performance of a V-cut on the tape insert. Experiments have been conducted on a double-pipe heat exchanger with nanofluid silicon dioxide as the working medium. This study encompasses a Reynolds number range of 6000–14,000. Notably, investigations reveal that the introduction of a v-cut on the tape engenders a secondary vortex flow. The enhancement in the Nusselt number at the higher Reynolds number for the primary vortex was observed ineffective as the depth of cut increases. The friction factor is increased by 6.37 times for the e/c ratio, which equals 0.17 (tooth to the depth of the v cut) in comparison to smooth pipe, while the increase in heat transfer rate for the same is 87.73% for Re = 6000.

Entropy production on mixed convection stagnation point flow of nonlinear radiative fourth-grade hybrid nanofluid through a stretchable Riga surface

The purpose of the current study is to inspect entropy generation, mixed convective stagnation point flow, and thermal transfer features of nonlinear radiative fourth-grade hybrid nanofluid (NF) confined by a convectively heated Riga surface. The heat transport is examined with the existence of two disparate heat source modulations, variable thermal conductivity, and viscous dissipation. The original flow equations are first transmuted using appropriate transformations into non-dimensional ordinary differential equations, which are then solved via an overlapping grid-based spectral collocation scheme. The upshots of various pertinent parameters on velocity, temperature, entropy generation, and valuable engineering quantities are deliberated. Pivotal results obtained reveal that speedily flow of fluid and skin friction can be accelerated by strong magnetic force, rising mixed convection, and material parameters. Also, convective boundary conditions, along with nonlinear radiation and fluctuating thermal conductivity, are recommended for boosting fluid temperature, rates of entropy generation and heat transport. Thermal mechanism in hybrid NF is dominant over simple NF, which implies that performance of hybrid NF is better than that of simple NF. The outcomes of this study can be useful in enriching thermal performance of the working fluid, assisting in diagnosing causes of incompetency in thermal systems, and discovering suitable means of minimizing entropy generation with the intention of mitigating the loss of useful and scarce energy resources.

Opto-mechatronic dynamic characteristics in iron oxide-based nanofluid using spatial and frequency domain analysis

Iron oxide nanoparticles (IONPs) exhibit low toxicity and high chemical stability, attractive for developing of nanofluids (NFs) for advanced medical applications. This research focuses on the study of the optical, mechanical, and electrical dynamics of iron oxide–ethanol NFs. A novel sensitive methodology for analyzing the influence of nanoparticles (NPs) over the optical and electrical processes exhibited by IONFs is reported. The IONPs were synthesized by a microemulsion route and were characterized by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. The NPs exhibit a mean diameter of 30 nm and they were identified as Fe2O3. UV–Vis spectroscopy allows us determining the volume fraction of the fluid as a function of time. The assistance of a Michelson interferometer integrated with an image processing methodology was employed to explore the dynamics of the nanostructures. The percentage of NPs involved in linear and nonlinear dynamic fluid processes was estimated by taking a double-stage (spatial and frequency domains) Fast Fourier Transform in the interferometric pattern. A DC voltage source was used to study the electrical conductivity of the NF as it was being sedimented. The opto-mechatronic parameters were correlated, considering the volume fraction as the main variable to determine the optical and electrical characteristics. For the Fe2O3 NF, it is identified that the linear effects of sedimentation present a stronger impact on the optical properties, while the nonlinear interactions have more influence on the electrical conductivity. The main findings of this research have potential applications in rheological instrumentation to analyze complex effects using transient opto-mechatronic components.

Improving the frictional properties of the tool/chip interface of micro-textured ceramics tools by using electromagnetic-assisted nanofluids

During the machining of stainless steel by ceramics tools, the tool/chip interface is difficult to be effectively cooled and lubricated due to the poor thermal conductivity of ceramic and stainless steel materials, resulting in the high cutting temperature and severe tool wear. To enhance the penetration of nanofluid into the tool/chip interface, a novel approach of magnetic field-assisted electroosmotic was proposed. The external magnetic field was introduced during the cutting process, and the self-excited electric field generated by intense tool/workpiece interface friction was considered. The effect of electromagnetic field-assisted Fe3O4 nanofluid lubrication on the cutting performance of micro-textured tool was investigated. The results showed that Fe3O4 nanofluid (NF) can be effectively migrated to the tool/chip interface driven by the electroosmotic force, Lorentz force and pressure to alleviate the tool wear. In particular, with increasing of electromagnetic field strength, the cutting performance was significantly improved. In addition, the mechanism of NF permeation at the micro-textured tool/chip interface under the electromagnetic field was revealed by combining the finite element simulation. This work provides a new method for efficient cooling and lubrication of the tool/chip interface during the machining of difficult-to-cut materials, and the drive theory of cutting fluid penetration is also enriched.