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Metal cutting, a complex process in manufacturing, involves various factors that significantly affect the quality of the final product. Notably, the turning process is crucial, with outcomes that heavily depend on multiple machining parameters. These parameters encompass speed, depth of cut, feed rate, the type of coolant used (specifically, high heat transfer MXene coolant), and insert types, among others. The material of the workpiece is also a critical factor in the metal-cutting operation. This study focuses on achieving optimal surface quality and minimizing cutting forces in the turning process. It recognizes the substantial impact of numerous process parameters, directly or indirectly affecting the product's surface roughness and cutting forces. Understanding these optimal parameters can lower machining costs and improve product quality. Our research concentrates on turning a stainless-steel alloy workpiece using a carbide insert tool. We employ the Response Surface Method (RSM) to optimize cutting parameters within a set range of cutting speed (100, 125, 150 m/min), feed rate (0.1, 0.2, 0.3 mm/rev), and depth of cut (0.4, 0.8, 1.2 mm). Additionally, we use various tool geometries and the RSM design of experiments to enhance and analyze the multi-response parameters of surface roughness and tool life. Optimal machining parameters for MXene-NFC involve a cutting speed of 140 m/min, a feed rate of 0.05 mm/rev, and a depth of cut of 0.5 mm. These settings ensure minimal surface roughness, maximum tool life, and the greatest total length of cut, achieving a composite desirability of 0.695. [ABSTRACT FROM AUTHOR]

Abstract In past decades, nanofluid science has been widely investigated for thermal related activities. In thermal transport applications, thermal conductivity and dynamic viscosity are closely related to cooling system performance enhancement. The genuine anomaly behind thermal conductivity and dynamic viscosity enhancement in nanofluid is still undiscoverable. In this paper, comprehensive study on principle factor behind thermophysical property enhancement focusing on thermal conductivity and dynamic viscosity is conducted. Thus, a detailed review of existing experimental results for thermal conductivity and dynamic viscosity enhancement are compiled and discussed in this manuscript. Analytical tool approach such as fishbone diagram and summary tables are used to highlight principle factor for thermal conductivity and dynamic viscosity enhancement. The principal factor which influences the thermal conductivity is shape of the particle, nanofluid preparation, interfacial layer, Brownian motion, particle clustering and aggregation. Meanwhile, the principal factor influencing dynamic viscosity is the physical behavior of the particle, nanofluid preparation, particle clustering and aggregation. The optimum nanofluid should have high thermal conductivity and minimum viscosity. High thermal conductivity is mandatory for maximum heat absorption in thermal transport applications. Meanwhile, minimum viscosity ensures less pressure drop which reduces the power consumption and increases the overall efficiency of the system. [ABSTRACT FROM AUTHOR]

Heating hybrid nanofluids by the mixing of solid nanoparticles suspended in liquid represents a new class of heat transfer enhancement. To enhance heat transfer for many industrial applications, a computational fluid dynamics modelling simulation using the finite volume method and adopting the SIMPLE algorithm was performed. The mixture of aluminium nitride nanoparticles into ethylene glycol which acts as a base fluid is considered as a new concept of hybrid nanofluids that can increase heat transfer. The hybrid nanofluid was prepared experimentally with a volume fraction range of 1% to 4%. The size diameter of nanoparticles, heat flux around a horizontal straight tube and Reynolds number is approximately 30 nm, 5000 w/m2 and 5,000 to 17,000, respectively. The computational method had been successfully validated using available experimental data reported in the literature. It was found that 1% to 3% Aluminum nitride hybrid nanofluids can significantly affect efficiency, while more than 3% volume fraction are insignificant as they obtain less than one efficiency. Results show that a combination of aluminium nitride nanoparticles with the EG base fluid tends to augment heat transfer performance significantly. [ABSTRACT FROM AUTHOR]

Modern nanotechnology can produce metallic or non-metallic particles of nanometer dimensions that have unique optical, mechanical, magnetic, electrical, and thermal properties. The purpose of this review is to summarise important published articles on the enhancement of convection heat transfer using nanoparticles dispersed in Ethylene Glycol (EG) and the effects on thermal properties and applications. This paper reviews all the articles relevant to nanoparticles suspended in EG. The studies of thermal properties including experimental measurement and correlations are reported. The effects of nanofluid volume fraction, temperature, and base fluid have been included. The stability of nanofluid was shown through testing to avoid agglomeration and clusters for many applications. In this paper, the applications of nanofluids in different types of heat exchangers, cooling systems, and solar energies are reviewed. In the field of economics, nanotech reduces manufacturing costs as a result of using a low-temperature process. In order to focus future studies of nanofluid applications, the articles on this field are summarized. [ABSTRACT FROM AUTHOR]

Highlights • Machining performances using ethylene glycol/nanocellulose based nanofluid. • 0.5 vol% EG/nanocellulose based MWF generates 1130 J of heat transfer at 30 °C. • Maximum temperature at chip formed by using nanofluid is 154 °C. Abstract In this paper, cellulose nanocrystal (CNC) – ethylene glycol (EG) + Water (W) based nanofluid was developed and assessed for their thermophysical properties and the usefulness towards machining performances. The nanofluid was prepared by adopting two-step preparation method and at volume concentration of 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1.1%, 1.3% and 1.5%. The nanofluid with 1.3% and 1.5% concentration showed to have superior the conductivity properties, around 0.559 W/m·K at 70 °C. However, the 0.5% concentration has the highest stability with 0.52 W/m·K at 70 °C. The 0.5% nanofluid concentration was then selected for the machining performance evaluation. The machining performance was evaluated by using a lathe machining operation to determine the heat transfer and tool life properties. The cutting variables such as cutting speed, depth of cut and feed rate are varied to understand the effect of developed nanofluid on the machining bahaviour. Findings revealed that the tool failure on machining using MWF is flank wear, chipping and abrasion and fractured at the maximum cutting distance of 500 mm. However, machining using CNC-EG+W nanofluid revealed the tool failure to be flank wear, adhesion and build- up-edge (BUE) and fractured at the maximum cutting distance of 772 mm. [ABSTRACT FROM AUTHOR]

Abstract: The increasing demand of nanofluids in industrial applications has led to increased attention from many researchers. In this paper, heat transfer enhancement using TiO2 and SiO2 nanopowders suspended in pure water is presented. The test setup includes a car radiator, and the effects on heat transfer enhancement under the operating conditions are analyzed under laminar flow conditions. The volume flow rate, inlet temperature and nanofluid volume concentration are in the range of 2–8 LPM, 60–80°C and 1–2% respectively. The results showed that the Nusselt number increased with volume flow rate and slightly increased with inlet temperature and nanofluid volume concentration. The regression equation for input (volume flow rate, inlet temperature and nanofluid volume concentration) and response (Nusselt number) was found. The results of the analysis indicated that significant input parameters to enhance heat transfer with car radiator. These experimental results were found to be in good agreement with other researchers' data, with a deviation of only approximately 4%. [Copyright &y& Elsevier]

Abstract: The low thermal properties of liquids have led to investigations into additives of small size (less than 100nm solid particles) to enhance their heat transfer properties and hydrodynamic flow. To summarise the experimental and numerical studies, this paper reviews these computational simulations and finds that most of them are in agreement with the results of experimental work. Many of the studies report enhancements in the heat transfer coefficient with an increase in the concentration of solid particles. Certain studies with a smaller particle size indicated an increase in the heat transfer enhancement when compared to values obtained with a larger size. Additionally, the effect of the shape of the flow area on the heat transfer enhancement has been explored by a number of studies. All of the studies showed a nominal increase in pressure drop. The significant applications in the engineering field explain why so many investigators have studied heat transfer with augmentation by a nanofluid in the heat exchanger. This article presents a review of the heat transfer applications of nanofluids to develop directions for future work. The high volume fraction of various nanofluids will be useful in car radiators to enhance the heat transfer numerically and experimentally. Correlation equations can expose relationships between the Nusselt number, the Reynolds number, the concentration and the diameter of the nanoparticles. On the other hand, more work is needed to compare the shapes (e.g., circular, elliptical and flat tube) that might enhance the heat transfer with a minimal pressure drop. [Copyright &y& Elsevier]

Abstract: The effects of the tube specifications on the heat transfer in car radiator are significant to improve cooling system performance. Friction factor and heat transfer enhancement of three types of nanofluids flow through horizontal three shapes of tubes has been evaluated numerically. CFD model by using FLUENT software depending on finite volume method was conducted. TiO2 nanoparticles with volume fractions (1%, 1.5%, 2% and 2.5%) are suspended in water as a base fluid to be nanofluids is used in this study. On the other hand, three types of tubes (circular, elliptical and flat tube) are chosen with 3mm hydraulic diameter and 500mm length. Numerical results show that the increase in volume fraction of nanofluid due to increase in fluid flow characteristics and heat transfer enhancement as compared with base fluid. The results of CFD model are compared with experimental data available in literature, and there is a good agreement with deviation 2%. [Copyright &y& Elsevier]

A new class nanofluid consisting of Copper Oxide (CuO) nanoparticles, Polyaniline Nanofibers (PANI), and CuO-PANI nanocomposites dispersed in refined, bleached, and deodorized palm olein (RBDL) base fluids have been successfully prepared. The prepared nanofluids were physically characterized to investigate the influence of different nanoparticles and nanocomposites on the dispersion behavior, thermal stability, and thermophysical properties. Physical characterization from TEM, EDX, XRD, TGA, and FT-IR analysis revealed that the CuO nanoparticles had been embedded in the PANI matrix. Sedimentation analysis revealed CuO/RBDL nanofluid achieved stability lesser than one month. Meanwhile, PANI/RBDL and CuO-PANI/RBDL showed there was no sedimentation for almost a month. UV–vis analysis further revealed that all PANI/RBDL and CuO-PANI/RBDL nanofluids samples achieved absorbance drop in the range of 4 to 12% after 30 days of evaluation. FT-IR analysis revealed that nanofluids are chemically stable. The thermal decomposition properties in the TG curve showed that the nanofluids could withstand high temperatures. Viscosity measurement revealed that all RBDL base nanofluids exhibited Newtonian behavior. The thermal conductivity measurement inferred that the most outstanding thermal conductivity was achieved by nanofluid with 10 wt% CuO-PANI nanocomposites with a 31.34% enhancement. While the least was shown by CuO/RBDL with 17.8% enhancement. [ABSTRACT FROM AUTHOR]

In this research work, MXene with a chemical formula of Ti 3 C 2 is synthesized using wet chemistry method and suspended in pure olein palm oil (OPO) to formulate a new class of heat transfer fluid to investigate its thermal and energy performance in a hybrid PV/T solar thermal system numerically using COMSOL Multiphysics. In addition to this research work, Al 2 O 3 -water based nanofluid is compared with MXene-OPO nanofluid in the hybrid PV/T solar thermal system. The MXene-OPO nanofluid is prepared with a loading concentration of 0.01, 0.03, 0.05, 0.08, 0.1, and 0.2 wt %. MXene-OPO nanofluid with 0.2 wt % loading concentration exhibit 68.5% higher thermal conductivity than the pure OPO at 25 °C. The highest viscosity reduction is found by 61% when the temperature is raised from 25 °C to 50 °C for nanofluid with 0.2 wt % of MXene. Compared to PVT with Al 2 O 3 -water based nanofluid, MXene based nanofluid display about 16% higher thermal efficiency improvement at 0.07 kg/s flow rate. About 9% heat transfer coefficient improvement is found for the PVT with MXene nanofluids compared to PVT with Al 2 O 3 -water heat transfer fluid. MXene nanofluid may reduce PV temperature by 40% compared to stand alone PV module. • Formulating MXene-OPO as a new class of nanofluids. • Higher heat transfer coefficient is found for the new nanofluid. • Improved heat transfer performance and photo-thermal conversion. • Excellent thermal efficiency in CPVT system is obtained. [ABSTRACT FROM AUTHOR]