Article
Engineering, Mechanical
Satish C. Sharma, Adesh Kumar Tomar
Summary: The study focuses on utilizing magneto-rheological fluid and micro-grooves to enhance the performance and stability of bearing systems, which is expected to assist in the design and analysis of bearing systems.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Mechanical
Mahdi Zare Mehrjardi, Asghar Dashti Rahmatabadi
Summary: This study presents the dynamic behavior of three-lobe noncircular hydrodynamic journal bearings lubricated with couple stress fluid and suggests solutions to improve rotor-journal bearing systems. By strengthening the couple stress properties of lubricant, the stiffness and damping ability of three-lobe bearings can be enhanced, leading to improved dynamic stability of rotor-bearing supports. The results also show that using noncircular three-lobe bearings and couple stress fluid instead of Newtonian lubricants can increase critical mass parameter and decrease whirl frequency ratio, enhancing the stability range of the bearings.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Article
Engineering, Mechanical
Anil Singh, Satish C. Sharma
Summary: This study focuses on the numerical investigation of the performance effects of geometric imperfections on a porous hybrid journal bearing system operating under turbulent flow conditions. The Reynolds equation governing the lubricant flow in the bearing space is modified using turbulent lubrication theory, and the performance parameters are computed using FEM. The combined effect of turbulent flow conditions and geometric imperfections results in enhanced values of performance indicators.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Krishnkant Sahu, Satish C. Sharma, Nathi Ram
Summary: Misalignment affects the operation of the journal bearing system, and smart lubricants can enhance the performance of fluid film bearings. The study finds that journal misalignment reduces the fluid film thickness, increases the fluid film damping coefficient, and frictional torque.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Shalini M. Patil, C. V. Vinay, P. A. Dinesh
Summary: This paper investigates the combined effects of nonNewtonian fluid and permeability on nonporous journal spinning within a rough porous bearing, finding that the pressure distribution and weight carrying capacity are more significant for nonNewtonian couple-stress fluid compared to the classical Newtonian case. The multigrid method for the Reynolds equation is used to accelerate convergence rate and promote enhanced pressure distribution in the fluid.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2021)
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.
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
Engineering, Mechanical
Shitendu Some
Summary: This theoretical investigation focuses on the steady-state pressure profile analysis of a hydrostatic double-layered porous journal bearing with Newtonian lubricant, considering the effect of turbulence. A modified Reynolds equation, derived based on the Beavers-Joseph's criterion for slip flow, is utilized to analyze finite porous journal bearings. The governing equations for flow in different layers of the porous medium and the modified Reynolds equation are solved simultaneously using the finite difference method, taking into account appropriate boundary conditions. The study presents the impact of various design parameters on the steady-state pressure profile of the bearing under both laminar and turbulent flow conditions, considering slip and no-slip conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2022)
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
Multidisciplinary Sciences
A. Ganesha, Albin Joseph, Raghuvir Pai, Shah Mohammed Abdul Khader, Nitesh Kumar, Shiva Kumar, H. Girish
Summary: The importance of preserving the ecological balance has led to the development of water lubricated bearings for various applications, including marine vessels. In this study, a water lubricated journal bearing model with a partial slip/no slip pattern was analyzed using CFD. The results showed that the number of grooves and groove angle are the most influential parameters affecting the load-carrying capacity of the bearing.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Mechanical
Krishnkant Sahu, Satish C. Sharma, Adesh Kumar Tomar
Summary: This paper proposes a study on the slot-entry 'hybrid conical journal bearing system' (HCJBs) with the slot restrictor as a compensating device. The effects of different zonal arrangements of textured surfaces and smart behavior of magnetorheological fluid (MRF) on the HCJBs are analyzed. Mathematical modeling of the modified Reynolds equation is done using the Finite element method and the Gauss-Seidel method. Numerical simulation shows that the application of textured surfaces and MR fluid improves the performance of the hybrid conical bearing system in terms of fluid film thickness, stiffness, and stability.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Shaoyu Zhu, Xiangjun Zhang
Summary: The modified average Reynolds equation for friction pairs with arbitrary three-dimensional rough surfaces lubricated by couple stress fluid is derived. The performance parameters under various factors, such as couple stress, surface roughness, journal misalignment, and thermal effect, are obtained using the finite difference numerical method. The results show that the surface roughness factor plays an important role in the performance of the friction pairs, even with small nominal eccentricity ratios.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Article
Engineering, Mechanical
Mohammad Tauviqirrahman, J. Jamari, Arjuno Aryo Wicaksono, M. Muchammad, S. Susilowati, Yustina Ngatilah, Caecilia Pujiastuti
Summary: In this study, a computational investigation into the acoustic and tribological performances in journal bearings is presented, using a heterogeneous pattern with rough surfaces engineered in certain regions. Numerical results show that heterogeneous rough/smooth bearings can provide lower noise and larger load-carrying capacity compared to conventional bearings, with discussions on the effects on friction force.
Article
Engineering, Aerospace
Peter L. Bishay, Christian Aguilar
Summary: Although the benefits of morphing wings have been proven in many studies, the conflicting design requirements of high out-of-plane stiffness and low in-plane stiffness remain a challenge for advancing morphing technology. Advances in hybrid and flexible composites may provide design solutions with a balance in stiffness. A parametric study of a composite skin for twist-morphing wings was conducted, considering design parameters such as the number of plies, fiber-orientation angle, and torsional rigidity. Analysis showed that torsional compliance can be increased by adjusting certain parameters, but at the expense of out-of-plane stiffness. The study highlights the nonlinear relationship and effects of different parameters on the behavior of the skin.
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)
