Article
Engineering, Chemical
Minghui Yang, Hong Lu, Xinbao Zhang, Meng Duan, Liu Bao, Bowen Wang, Wan Wu
Summary: The waviness of the journal and bearing bush surfaces can have different effects on the hydrodynamic journal bearing system. The profile of the surfaces near the attitude angle plays a significant role in determining the performance of the bearing system.
Article
Mechanics
Chandra B. Khatri, Saurabh K. Yadav, Gananath D. Thakre, Arvind K. Rajput
Summary: This paper investigates the application of a vein bionic texture inspired by a peepal leaf pattern to the surface of a hydrodynamic journal bearing, with the optimization done by a bio-inspired genetic algorithm. The study found that the use of the bionic texture alone increased the stability parameter by 13.08% and reduced the friction torque by 21.17%. However, the use of the GA-optimized vein-bionic texture resulted in even greater improvements, with the stability parameter increasing by up to 18.24% and the friction torque being reduced by up to 46.66%. The findings of this study are valuable for researchers in rotor dynamics seeking to stabilize systems with the use of GA-optimized vein-bionic textured journal bearings.
Article
Engineering, Mechanical
He Li, Junkai Niu
Summary: This paper investigates the impact of texture on the tribological performance of journal bearings operating under starvation lubrication conditions. The P-theta model with mass conservation boundary conditions accurately predicts the oil film distribution in the full oil film/starvation region of the textured bearing. The study discusses the effects of different levels of starvation lubrication on parameters such as eccentricity, attitude angle, full film area, and friction coefficient in textured bearings. The results show that the severity of the texture's effect on bearing performance varies with starvation levels and that texturing can improve the bearing's operating performance, increase load carrying capacity, reduce friction coefficient, and enhance safety.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2023)
Article
Engineering, Mechanical
G. H. G. van der Meer, F. Quinci, W. Litwin, M. Wodtke, R. A. J. van Ostayen
Summary: The study investigates the application of a modified MR fluid in lubrication performance using a journal bearing test bench. It is found that applying a local magnetic field can significantly reduce the transition speed of the bearing when lubricated with MR fluid, with only a minimal increase in friction. The lubricating performance of the MR fluid is compared to a reference oil.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Yazhou Mao, Lilin Li, Daqing Li, Jingyang Zheng
Summary: This paper investigates the turbulent lubrication performance of a textured hydrodynamic journal bearing (THJB) and analyzes the effects of structural and working parameters on the bearing performance. The results show that turbulent lubrication is suitable for actual operating conditions, but the system tends to be unstable as the eccentricity ratio and rotational speed increase.
Review
Green & Sustainable Science & Technology
Z. Rasep, M. N. A. W. Muhammad Yazid, S. Samion
Summary: Vegetable oils are seen as potential bio lubricants that could replace traditional mineral oils in the future, offering unique environmental benefits. Surface modification of journal bearings has gained attention for its ability to enhance performance. The combination of textured journal bearings and vegetable oil shows promise for various industrial applications.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Engineering, Mechanical
Debajit Das, Sashindra Kumar Kakoty
Summary: This paper investigates the effects of lubricant inertia on the performance parameters of journal bearings textured with spherical-shaped textures. The results show that lubricant inertia significantly improves the performance characteristics of textured journal bearings, especially in heavily loaded bearings. Additionally, it is found that protruded texturing produces better results compared to dimple textured journal bearings.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2023)
Article
Engineering, Mechanical
Sanjay Sharma, Aniket Sharma, Gourav Jamwal, Rajeev Kumar Awasthi
Summary: This comparative numerical study analyzed the performance of V-shape protruded, dimple textured, and untextured bearings, finding that the load-carrying capacity and coefficient of friction are maximized for the protruded textured bearing under certain conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Mechanics
Peng Li, Hao Zhang, Xin Li, Zhanqun Shi, Sen Xiao, Fengshou Gu
Summary: The paper investigates the effect of manufacturing errors and misalignment on the lubrication behavior of journal bearings with micro-groove under dynamic loads. A mixed lubrication model is developed, considering factors such as mass conservation cavitation algorithm, asperity contact model, and force balance equation. The performance parameters of bearings with different surface profiles and micro-groove distributions are analyzed, and the results show that manufacturing errors and misalignment have a significant impact on the transient behavior of journal bearings.
Article
Engineering, Mechanical
Qinggang Guo, Long Zheng, Yinghui Zhong, Shukun Wang, Luquan Ren
Summary: Numerical models of continuous groove textures with X-shaped units were established in this study. The effects of geometric parameters and sliding speed on tribological properties were systematically investigated. The optimal geometric parameters for each texture shape were determined. It was found that the circular texture exhibited the best lubrication performance at lower area densities, while the square texture with a groove depth increase and an orientation of theta = 90 degrees showed better tribological performance when the area density exceeded 25%. The lubrication mechanism was explained as a trade-off between fluid flow and the generation of hydrodynamic pressure.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Engineering, Mechanical
Nayab Rasool Syed, Sashindra Kumar Kakoty
Summary: The study focuses on textured hydrodynamic bearings and the numerical solution of these bearings. The use of progressive mesh densification (PMD) method to estimate performance parameters is explored and compared with other methods. The PMD method is found to be highly effective in improving computational efficiency.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Chemical
Arun Bangotra, Sanjay Sharma
Summary: This paper presents the static performance analysis of journal bearing with full and partial surface waviness. The effect of surface waviness is considered by modifying the Reynolds equation with the film thickness equation and solved using the finite element method. The study investigates the bearing load capacity, friction coefficient, and other performance parameters under eccentricity ratios ranging from 0.2 to 0.8. Results show that the maximum performance is achieved in the circumferential direction of the full and pressure-increasing region at a high eccentricity ratio.
LUBRICATION SCIENCE
(2023)
Article
Engineering, Mechanical
Kazuyuki Yagi, Wataru Matsunaka, Joichi Sugimura
Summary: This study investigates the effect of textured patterns on lubrication performance in starved hydrodynamic lubrication. Longitudinal or transverse grooves on discs are found to improve lubricant supply into the lubricated area at high sliding conditions, compared to a flat disc.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
F. Quinci, W. Litwin, M. Wodtke, R. van den Nieuwendijk
Summary: The study investigates the performance of a journal bearing lubricated with magnetorheological fluid using Finite Element Modelling (FEM) and experiments. Thicker fluid films, beneficial pressure distribution, and higher friction losses are observed in the bearing with magnetorheological fluid compared to oil lubrication, under all operating conditions.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Jiahao Shi, Bin Zhao, Tao He, Liyue Tu, Xiqun Lu, Hanzhang Xu
Summary: This study aims to establish a thermal elastohydrodynamic (TEHD) lubrication analysis model for textured journal-thrust coupled bearing in diesel engine, taking into consideration the thermal and pressure coupled effects in the lubrication process. The model considers the flow, pressure, and thermal continuity conditions between the journal and thrust parts. Experimental results from a specific testing equipment validated the correctness of the TEHD lubrication model. Parametric analyses were conducted to explore the influences of thermal and pressure coupled effects on lubrication performances and dynamic characteristics.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Thermodynamics
Ashutosh Kumar Singh, Kuldeep Singh, Dushyant Singh, Niranjan Sahoo
Summary: The study investigated the film cooling performance of cylindrical and reverse shaped holes for forward and reverse injection configurations using large eddy simulations, showing that the reverse shaped hole outperforms the cylindrical hole in terms of cooling effectiveness.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Vijay Kumar, Rajeev Verma, Saurabh Kango, Vishal S. Sharma
Summary: Laser surface texturing is a well-known technique for enhancing the surface topography of engineering materials, and has been widely applied in areas such as lubrication, wear behavior, and surface contact.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Thermodynamics
Hitesh Sharma, Dushyant Singh, Ashutosh Kumar Singh
Summary: The study showed that higher mainstream Mach numbers resulted in increased wall temperature and reduced effectiveness, while increasing the coolant stream Mach number led to significant improvement in film cooling effectiveness.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2021)
Review
Engineering, Mechanical
Nitin Sharma, Rajeev Verma, Sumit Sharma, Saurabh Kango
Summary: This article systematically reviews previous studies on the successful implementation of surface textures and coatings in fluid film bearing systems to improve tribological performance, with a focus on understanding the physical causes behind the success of these methods.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2021)
Article
Energy & Fuels
Kedumese U. Mekrisuh, Shubham Giri, Udayraj, Dushyant Singh, Dibakar Rakshit
Summary: Phase change materials (PCM) play a crucial role in thermal energy storage (TES) systems as storage materials. Different enhancement techniques such as fins, nanoparticles, and hybrid methods are utilized to improve the thermal performance of TES systems. The study demonstrates that optimizing geometric parameters can significantly enhance the thermal performance of TES systems compared to relying solely on enhancement techniques.
JOURNAL OF ENERGY STORAGE
(2021)
Article
Engineering, Mechanical
Mohammad Arif, Saurabh Kango, Dinesh Kumar Shukla
Summary: This study investigated the influence of slip zone locations on the dynamic stability of hydrodynamic journal bearings lubricated with non-Newtonian and Newtonian lubricants. The results showed that the interface of slip and no-slip regions near the upstream side of minimum film-thickness location can improve the dynamic performance parameters of the bearings. Additionally, shear-thinning lubricants combined with slip boundary conditions exhibited higher dynamic stability compared to Newtonian lubricants under conventional boundary conditions.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2022)
Article
Thermodynamics
Dushyant Singh, Ayush Kumar Rao, Udayraj
Summary: This study focuses on the numerical investigation of a passive horizontal base heat sink with perforated fins. The study found that the thickness ratio, size of square perforation, and number of perforations significantly affect the heat transfer coefficient in the trapezoidal cross-section fins. A 11.7% increment in heat transfer coefficient was observed in the perforated heat sink compared to the non-perforated heat sink. The mass of the passive heat sink decreases with an increase in the size and number of perforations, as well as a decrease in the thickness ratio, with a reduction of up to 58%.
HEAT TRANSFER ENGINEERING
(2022)
Article
Physics, Multidisciplinary
Shivam Verma, Saurabh Kango, Ashok Kumar Bagha, Shashi Bahl
Summary: This paper proposes a finite element model updating algorithm to enhance the accuracy of the simulated finite element model of a smart structure. The direct updating algorithm is used to reduce uncertainties in the structure. It is found that updating the mass and stiffness matrices successfully improves the accuracy of the finite element model.
Article
Thermodynamics
Dushyant Singh, Udayraj, Ashutosh Narayan Singh, Jishnu Handique
Summary: This study focuses on the investigation of fluid flow and heat transfer caused by the impingement of an unconfined turbulent slot jet on a smooth flat plate through experimental and large-eddy simulation. The results show that the change in Reynolds number, nozzle-to-plate spacing, and non-dimensional slot width has a significant impact on the stagnation point and wall jet Nusselt numbers. Turbulent kinetic energy plays a major role in enhancing the heat transfer rate, and its dissipation increases with increasing nozzle-to-plate spacing and non-dimensional slot width. A correlation is proposed for the stagnation point and wall jet region Nusselt numbers in terms of the effect of slot width, Reynolds number, and non-dimensional nozzle-to-plate spacing.
EXPERIMENTAL HEAT TRANSFER
(2022)
Article
Engineering, Mechanical
Mohammad Arif, Saurabh Kango, Dinesh Kumar Shukla
Summary: This study investigates the combined influence of slip boundary condition and non-Newtonian lubricants on the tribological performance of hydrodynamic textured journal bearing. The modified Reynolds equation with considering the Elrod cavitation model is solved to accurately predict the effect of air/vapor bubble formation in the diverging zone of the slip-texture bearing. The results show that changing the rheology of the lubricant from Newtonian to Pseudoplastic significantly improves the maximum pressure, average rise in temperature, and lubricant-bearing friction-force of the slip-texture bearings.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Thermodynamics
Ashutosh Kumar Singh, Kuldeep Singh, Dushyant Singh, Niranjan Sahoo
Summary: This study proposes a suitable injection configuration and operating parameters for film cooling of an aero-engine afterburner through experimental and numerical investigations. The research reveals that the film cooling on a corrugated surface is influenced by the secondary stream injection locations and corrugation amplitude to wavelength ratio. It also shows that film cooling behavior on a corrugated surface is inherently different from that on a flat surface, with improvements even at higher blowing ratios.
EXPERIMENTAL HEAT TRANSFER
(2022)
Article
Engineering, Mechanical
Jitendra Satyarathi, Vijay Kumar, Saurabh Kango, Rajeev Verma, Nitin Sharma, Rajeev Gupta
Summary: The present study aimed to fabricate superhydrophobic surfaces on low carbon steel through laser surface texturing and various modification methods. The mechanical stability and durability were evaluated and the results showed that the samples treated with chemical etching exhibited the best superhydrophobic properties.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2022)
Article
Thermodynamics
Ashutosh Kumar Singh, Kuldeep Singh, Dushyant Singh, Niranjan Sahoo
Summary: Based on experimental and numerical studies, an effective injection configuration for film cooling applications on sinusoidal corrugated surfaces is proposed. The experimental study shows that the (L-50-L-75) injection case has the best performance.
EXPERIMENTAL HEAT TRANSFER
(2023)
Article
Engineering, Chemical
Sartaj Singh, Saurabh Kango
Summary: The present study investigates the combined use of micro-textures and 'wettability gradient' on the thermohydrodynamic performance of inclined slider bearings. Using the Elrod cavitation model with slip boundary condition, the dimensionless static performance parameters were evaluated at different convergence ratios and sliding speeds. Results showed that the slip-textured bearings exhibited improved load carrying capacity, friction force, and volumetric inflow rate, particularly at smaller convergence ratios. The square textured slip bearing showed the maximum improvements across various performance parameters.
LUBRICATION SCIENCE
(2023)
Article
Thermodynamics
Dushyant Singh, Chunkyraj Khangembam, Kuldeep Singh, Ketan Atulkumar Ganatra
Summary: This study focuses on the investigation of air-water mist jet impingement heat transfer on a heated flat plate through experimental and numerical methods. The results show that increasing the mist loading fraction and Reynolds number can enhance the heat transfer rate, while increasing the plate-to-nozzle distance decreases the heat transfer rate. Significant increases in the Nusselt number are also observed. Correlation models are proposed to explain these findings.
HEAT AND MASS TRANSFER
(2023)
