A simplified structural model of bump-type foil bearings based on contact mechanics including gaps and friction

Arghir, Mihaï; Benchekroun, Omar

doi:10.1016/j.triboint.2019.01.038

Cited by 40 publications

(23 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For samples 2 and 6, the following can be noted: with an increase in mol.% Y2O3 (from 2.031 mol.% to 2.036 mol.%) and mol.% CeO2 (from 0.435 mol.% to 0.653 mol.%) and a corresponding decrease in mol.% Nd2O3 (from 0.334 mol.% to 0.111 mol.%), a decrease in microhardness is observed. This trend can be traced when comparing samples No 6. and No.…”

mentioning

confidence: 80%

See 1 more Smart Citation

Improving the mechanical properties of zirconia in instrument bearings

Alisin

Diethelm²,

Kulebyakin

et al. 2020

MATEC Web Conf.

View full text Add to dashboard Cite

The article presents the issues of replacing leucosapphires in jeweled bearings of the axes of precision instruments with nanostructured crystals of partially stabilized zirconia. The statement is substantiated that doping with rare earth elements provides an improvement in the performance properties of precision instruments by improving the mechanical properties of bearing materials. The efficiency of doping of zirconia crystals with cerium and neodymium oxides is studied. It was found that doped crystals have increased plasticity, which provides an increase in the crack resistance of crystals. Special attention is paid to the issues of increasing the survivability of high-speed rotor bearings by replacing the thrust bearing of leucosapphire with nanostructured crystals of partially stabilized zirconia doped with cerium and neodymium. The efficiency of improving the mechanical properties is confirmed by the X-ray phase analysis of crystals. The phase composition is studied by Raman scattering and the lattice parameters are determined. The increased crack resistance of the thrust bearing is confirmed by tests performed using the kinetic microhardness method.

show abstract

mentioning

confidence: 80%

“…The nonlinear dynamic behavior of a rigid rotor interacting with different types of support bearings has been studied [5]. The stability of the rotor at high speeds is considered in paper [6]. The paper [7] studies the possibility of adjusting the rotor bearings.…”

Section: Introductionmentioning

confidence: 99%

Improving the mechanical properties of zirconia in instrument bearings

Alisin

Diethelm²,

Kulebyakin

et al. 2020

MATEC Web Conf.

View full text Add to dashboard Cite

show abstract

“…Hu and Feng [24] presented a beam model of the bump foil by considering the rounding radius of the bump to study the effect of rounding radius on the static performance of GFBs. Recently, Arghir and Benchekroun [25] further developed the foil model introduced in [17] by modeling the closeloose contacts between the top foil and the bump foil to consider possible gaps and manufacturing errors in the foil structure. This foil model was then coupled with the gas film model to determine all operating conditions of GFBs from start-up to full speed [26].…”

Section: Introductionmentioning

confidence: 99%

An efficient three-dimensional foil structure model for bump-type gas foil bearings considering friction

Lan

Ren

et al. 2020

Friction

View full text Add to dashboard Cite

This paper presents an efficient three-dimensional (3D) structural model for bump-type gas foil bearings (GFBs) developed by considering friction. The foil structures are modeled with a 3D shell finite element model. Using the bump foil mechanical characteristics, the Guyan reduction and component mode synthesis methods are adopted to improve computational efficiency while guaranteeing accurate static responses. A contact model that includes friction and separation behaviors is presented to model the interactions of the bump foil with the top foil and bearing sleeve. The proposed structural model was validated with published analytical and experimental results. The coupled elastohydrodynamics model of GFBs was established by integration of the proposed structural model with data on hydrodynamic films, and it was validated by comparisons with existing experimental results. The performance of a bearing with an angular misalignment was studied numerically, revealing that the reaction torques of the misaligned bearing predicted by GFB models with 2D and 3D foil structure models are quite different. The 3D foil structure model should be used to study GFB misalignment.

show abstract

“…[25] had the advantage of less computational effort. Therefore, it was recently extended for taking into account close-loose contacts between the foils, the bearing sleeve, and the rotor [31]. The top foil stiffness and an additional degree-of-freedom (DOF) per bump were added.…”

Section: Introductionmentioning

confidence: 99%

“…The new model and the employed numerical algorithms are detailed in Ref. [31]. Arghir and Benchekroun [31] present the results for the stiffness of the whole compliant structure obtained by pushing the rotor against the bearing.…”

Section: Introductionmentioning

confidence: 99%

A New Structural Bump Foil Model With Application From Start-Up to Full Operating Conditions

Arghir

Benchekroun

2019

Journal of Engineering for Gas Turbines and Power

Self Cite

View full text Add to dashboard Cite

This paper presents a new structural bump foil model that can handle all operating conditions from start-up to full speed. The model is based on a nonlinear contact algorithm with friction and gaps. The top foil is modeled as a curved beam while bump foil uses a coupled truss model. The model considers the gaps between the bump foil and the bearing casing, between the bump foil and the top foil and between the rotor and the top foil. Thus, any numerical interference between the rotor and the top foil is avoided. A mixed lubrication model is used for the thin film pressures. Following this algorithm, contact pressures appear if the film thickness is less than three times the equivalent roughness of the rotor and of the top foil. Fluid pressures are calculated from numerical solutions of Reynolds equation while contact pressures, if present, are calculated with the model of Greenwood and Williamson. The model is validated by comparisons with the experimental results obtained for start-up operating conditions of a first-generation foil bearing of 38.1 mm diameter with static loads of 10–50 N. Theoretical predictions of the start-up torque and takeoff speed compare well with experimental results. It is also shown how manufacturing bump height errors can explain the differences between theoretical and experimental predictions. Further validations are presented for the same bearing operating at high speeds (30, 45, and 55 krpm) and heavy static loads (up to 200 N). The calculated minimum film thickness and attitude angle are compared with experimental data from the literature.

show abstract

A simplified structural model of bump-type foil bearings based on contact mechanics including gaps and friction

Cited by 40 publications

References 34 publications

Improving the mechanical properties of zirconia in instrument bearings

Improving the mechanical properties of zirconia in instrument bearings

An efficient three-dimensional foil structure model for bump-type gas foil bearings considering friction

A New Structural Bump Foil Model With Application From Start-Up to Full Operating Conditions

Contact Info

Product

Resources

About