Enhancing biodegradable lubricants with SiO₂ and TiO₂ nanoparticles: effects on viscosity, tribological behavior, rheological performance, and sustainability

Biomass Conversion and Biorefinery, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Language: Английский

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Assessment on Oxidative Stability and Tribological Response of Ficus Carica Oil, Enhanced with TBHQ and EVA Additives

Tribology International, Journal Year: 2025, Volume and Issue: unknown, P. 110735 - 110735

Published: April 1, 2025

Language: Английский

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Experimental study of exergy-energy performance of stabilized carboxyl-hydroxyl MWCNT/water nanofluids as operating fluid of plate heat exchanger

Journal of Industrial and Engineering Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Language: Английский

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Experimental Visualization Study of Two-Phase Flow Dynamics in Closed-Loop Pulsating Heat Pipes Using Fe₃O₄/Water

Published: July 2, 2024

This article discusses a focused study on visualizing the flow patterns in two-phase pulsating heat pipe (PHP) using Fe3O4/water as working fluid at 3 V/V% concentration. The research also aims to meticulously examine phase change phenomena heating section, particularly focusing bubble formation and expansion processes. A high-speed video camera was utilized capture dynamic insights into behavior of mixture. Based findings, straightforward model developed explain generation growth mixture, serving useful reference for future PHP designs optimizations. Visual observations noted stable nature nanofluid over four-day period, confirming its consistency throughout experiments. Moreover, impact load variation evaporator section assessed controlled inputs ranging from 10 80 Watts. Observations arrangement slugs plugs 50% filling ratio revealed interesting self-adjusting response increasing inputs, providing valuable operational dynamics. Notably, oscillatory Fe3O4/water, chosen fluid, exhibited greater activity comparison water. distinctive contributed achieving heightened thermal performance efficiency system, attributed faster attainment annular condition.

Language: Английский

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Experimental Investigation of the Thermophysical and Tribological Properties of Nano-TiO2-MnO2-Doped Graphene Oxide/Base Oil Ternary Hybrid Nanofluids

Arabian Journal for Science and Engineering, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 25, 2024

Language: Английский

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CFD-Based Performance Analysis of Hybrid MWCNTs–SiO₂ Nanofluids in Plate Heat Exchangers: Enhancing Heat Transfer with Minimal Pressure Drop

Published: Aug. 21, 2024

Heat exchangers play a vital role in numerous sectors like power generation and automotive manufacturing. Enhancing the energy efficiency of these stands as significant hurdle. Utilizing nanofluids emerges an optimal solution to augment heat transfer rates, leveraging their superior thermal conductivity while addressing economic constraints linked with traditional exchanger technologies. The motivation for this study is consider comprehensive synergistic features MWCNTs, SiO2, hybrid MWCNTs–SiO2 EG-based plate exchangers. This was achieved by simulating using CFD (Fluent Gambit softwares) considering comparison two forms at different mass concentrations. Reynolds-Averaged Navier-Stokes (RANS) method employed model turbulent flows, nanoparticles were compared both single-phase two-phase states, properties derived from experimental studies. Moreover, Nusselt number, convective coefficient, pressure drop variations computed Reynolds numbers. findings indicated increase number incorporation nanofluid, achieving maximum enhancement 11.19% EG 240 concentration 0.86 wt.%. Noticeably, remained negligible lower numbers, exhibiting marginal up 0.3% higher At wt.% 480, introduction hybrid, SiO2 nano-additives resulted respective increases coefficient 21.02%, 10.76%, 2.16% corresponding alterations 0.11%, 0.04%, 0.02%.

Language: Английский

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A Comparative Study of Theoretical and Experimental Analysis on Balanced and Unbalanced Rotors Supported by Oil- and Water-Lubricated Journal Bearings

Machines, Journal Year: 2024, Volume and Issue: 12(10), P. 675 - 675

Published: Sept. 26, 2024

Studying rotor-bearing systems involving fluid film bearings is essential for designing and assessing the dynamic responses performance of rotating machinery. They are involved in many applications such as pumps, turbines, engines. Water-lubricated often used where use oil-based lubricants not desirable, environmentally sensitive areas water desalination. In this study, analysis performed to identify stability regions that prevent application water-lubricated journal bearings. This achieved by solving system equations motion then using an infinitesimal perturbation method evaluate second-order bearing coefficients a bearing. paper, steel shaft supported two symmetrical was investigate analysis. A test rig designed manufactured examine rotor’s behavior verify theoretical outcomes FE model, utilizing based on Furthermore, study compares fluids, both theoretically experimentally, investigating their impact at different rotational speeds. The findings indicate threshold speed significantly higher when lubricant compared oil fluid. Additionally, because low viscosity water, susceptible significant wear noise operating conditions. Our experiments show provides less response than unbalanced rotors within tested range.

Language: Английский

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Study on the Effect of Thermal Characteristics of Grease-Lubricated High-Speed Silicon Nitride Full Ceramic Ball Bearings in Motorized Spindles

Lubricants, Journal Year: 2024, Volume and Issue: 12(8), P. 286 - 286

Published: Aug. 14, 2024

Grease lubrication is cost-effective and low-maintenance for motorized spindles, but standard steel bearings can fail at high speeds. This study focuses on high-speed full ceramic ball lubricated with grease. The coefficient of friction torque in the empirical formula corrected by establishing heat generation model bearing combining it experiments. A simulation grease flow established to influence filling amount distribution. temperature field a analyze rotating speed generation, experiments verify calculation results theoretical model. show that an optimal 15~25% ensures even distribution without accumulation. Additionally, when constant, outer ring increases higher test 0.9~1.2 g, accounts about 9~12% volume cavity, lowest. At rotation 24,000 rpm, grease-lubricated 50.1 °C, indicating reasonable range use spindles. It provides basis optimization design macro-structural parameters future, which minimize maximize capacity.

Language: Английский

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Research on the Correlation between Mechanical Seal Face Vibration and Stationary Ring Dynamic Behavior Characteristics

Lubricants, Journal Year: 2024, Volume and Issue: 12(9), P. 316 - 316

Published: Sept. 12, 2024

To address the lack of reliable measurement methods for identifying wear mechanisms and predicting state mechanical seal tribo-parts, this study proposes a method characterizing tribological behavior based on measuring face vibration acceleration. It aims to uncover source mechanism acceleration influenced by tribology dynamic behavior. This research delves into characteristics stationary ring. We explored variation pattern root mean square (RMS) with rotation speed, sealing medium pressure, surface roughness. The results indicate that under constant an increase in speed leads decrease RMS temperature. Similarly, pressure nonlinear changes RMS, forming “M” shape, along Furthermore, conditions roughness rotating ring corresponds Upon starting seal, both temperature initially before decreasing, trend consistent Stribeck curve.

Language: Английский

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Exploring the additive compatibility and tribological behavior of regular and high oleic soybean oil

Frontiers in Mechanical Engineering, Journal Year: 2024, Volume and Issue: 10

Published: Nov. 25, 2024

As the demand for biobased lubricating oils continues to rise, there is a growing focus on exploring diverse oil types. Particularly noteworthy surge in high oleic oils, which offer enhanced stability, and richer acid content compared their regular counterparts. However, performance of soybean (HOSO) with additives (RSO), remains unclear. This study focused revealing compatibility both (RSO) select antiwear antioxidant additives, specifically zinc dialkyl dithiophosphate (ZDDP), dithiocarbamate (ZDDC) combined antimony dialkyldithiocarbamate (ADDC), along comparative analysis these additives. Reciprocating friction, wear, electrical contact resistance-based analyses were conducted evaluate additive wear mechanisms at room temperature lubrication conditions. Interestingly, it was observed that better than (HOSO). RSO showed around 28% reduction volume whereas, only 8% HOSO Additional physiochemical property lubricants correlate tribological behavior. The worn-out surfaces test samples characterized thoroughly reveal dominant mechanisms.

Language: Английский

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