...Che Wang; Zhaodong Zhang; Yuhua Huang; Zibo Zhao; Hua Zhong; Jianhua Wu The journal bearing is pivotal for the advancement of refrigerant compressors. While the gas–oil lubrication mechanism has been explored in some previous studies, the dynamic coefficients of gas–oil-lubricated bearings...

...Chunxing Gu; Li Dai; Di Zhang In order to explore the influence of different acceleration and deceleration forms on the bearing performance during acceleration and deceleration, an isothermal and mixed lubrication model for journal bearings was established. In this model, the fluid mechanics...

...Xun Huang; Ge Xu; Shuyun Jiang Journal bearing reaction is usually represented by a set of forces and moments concentrated at a single point. This single point support model cannot be utilized to describe the behavior of fairly long bearing. This technical brief proposes a multiple nodes model...

...Shanshan Wei; Yuri Kligerman; Roman Goltsberg; Izhak Etsion A computational fluid dynamics analysis of two-phase flow was used to obtain the distribution of lubricant in a journal bearing, including inlet tube and groove. It was found that for an incomplete starting film, the oil spread-length...

...Surojit Poddar; N. Tandon This present article evaluates the state of starvation in a journal bearing using acoustic emission (AE) and vibration measurement techniques. A journal bearing requires a constant supply of oil in an adequate amount to develop a hydrodynamic film, thick enough to separate...

...Changmin Chen; Jianping Jing; Jiqing Cong; Zezeng Dai; Jianhua Cheng The position of fluid film in journal bearing will change while the journal moving in bearing, which can be named fluid film boundary migration (FFBM). It is usually ignored in the calculation of linear dynamic coefficients. While...

...Chunxing Gu; Xianghui Meng; Shuwen Wang; Xiaohong Ding Surface texturing is one effective means to improve bearing performance. Available studies are mainly focused on the perfectly aligned journal bearing with textures. The studies involving the effect of surface texturing on the misaligned...

...) by the finite-difference method, the mesh density is the key to ensure the accuracy of the calculation results. In order to determine the reasonable number of differential meshes, the journal bearing in Table 2 (Re A = 2486.9, ɛ 0 = 0.6, γ = 0.06 deg, W = 10 m/s at s = 0 mm) is studied...

... the spreadability of additive manufacturing materials. While the load carrying capacity of granular flows has been previously demonstrated, this work attempts to more directly uncover the hydrodynamic-like granular flow behavior in an experimental journal bearing configuration. An enlarged granular lubricated...

... conducted using the Pprime Institute bearing test rig. The performance of the same two-lobe journal bearing (preload 0.524) as used in a previous study, lubricated with ISO VG 46 oil, was evaluated. Scratches of different depths (varying as a function of the radial clearance) were directly machined onto...

... of lubricated bearings? The answer is yes, being the volumetric heat capacity an important parameter. In this work, the static behavior of journal bearings is studied when nanoparticles are added to the lubricant. A thermohydrodynamic analysis is performed with oil ISO VG68 (base fluid) and six different...

... Bearings for Maximum Static Stiffness ,” J. Appl. Mech. , 57 , pp. 758 – 761 . 10.1115/1.2897088 [3] Gad , A. M. , Nemat-Alla , M. M. , Khalil , A. A. , and Nasr , A. M. , 2006 , “ On the Optimum Groove Geometry for Herringbone Grooved Journal Bearings ,” J. Tribol. , 128 , pp...

... analysis of the short journal bearing is developed. Pressure profiles and linearized stiffness, damping and mass coefficients are calculated for different operating conditions. A time transient solution is developed. The change in the rotor displacements when subjected to unbalance forces is explored...

...T. V. V. L. N. Rao The purpose of this paper is to present the linearized stability analysis of two-layered fluid film in the journal bearing. In this work, a modified classical Reynolds equation is derived under dynamic conditions consisting of two layers of fluid film described by Newtonian...

...Roberto Bassani This chapter deals with a hydrodynamic journal bearing provided with hollow bushings, capable of supporting very high loads, even at low speeds, at which separation between the shaft and the housing’s bushing is induced by a specific self-regulating hydrostatic system. The same...

... layer between contacting bodies with a specified gap conductance to partition the frictional heat. Application of the model to the heat transfer analysis of journal bearing systems experiencing oscillatory motion is presented. Nonuniformly distributed frictional heat along the axial direction...

... was developed to predict bearing performance under the mixed lubrication condition in microgrooved journal bearings. Oil film thickness distributions, hydrodynamic and contact pressure distributions, and real contact area between the journal surfaces and the bearing surfaces with microgroove were obtained...

...R. K. Naffin; L. Chang This paper presents an analytical model for the basic design calculations of plain journal bearings. The model yields reasonable accuracy as compared with published numerical solutions under the same conditions. The principles and procedures of the formulations are presented...

...Jun Sun; Mei Deng; Yonghong Fu; Changlin Gui Journal misalignment exists generally in journal bearings. When severe journal misalignment takes place, the minimum film thickness of journal bearings reduces greatly. In this condition, the surface roughness, the oil viscosity-pressure relationship...

...Hiromu Hashimoto; Masayuki Ochiai This paper describes the stabilization method for small-bore circular journal bearings using starved lubrication. First, we describe the experimental examination to confirm the effect of supply oil conditions on stability of circular journal bearing by using a high...