Abstract
This paper deals with the effect of journal misalignment on the load capacity of a multi-pad externally adjustable bearing. Pad adjustments can be provided in radial and tilt directions. A modified film thickness equation is applied to determine the variation in film thickness under different pad adjustment conditions. Governing Reynolds equation is discretized using finite difference approximation technique. In the present study, misalignment is considered in only one plane. Variation in load capacity is analyzed for different degrees of misalignment and pad adjustment positions. An improvement in the bearing load capacity is observed by applying a combination of negative radial and negative tilt adjustment to the four bearing pads.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Abbreviations
- C :
-
Radial clearance (m)
- DM:
-
Degree of misalignment
- R :
-
Journal radius (m)
- R adj :
-
Radial pad adjustment
- e :
-
Eccentricity (m), \(\varepsilon = \left( {e| C} \right)\)
- F :
-
Friction force (N), \(\overline{F} = \left( {F|LCp_{\text{s}} } \right)\)
- h :
-
Lubricant film thickness (m), \(\bar{h} = \left( {h | C} \right)\)
- L :
-
Bearing length (m)
- N′:
-
Journal speed (rps)
- \(p\) :
-
Constant supply pressure (N/m2)
- \(p_{\text{s}}\) :
-
Static film pressure (N/m2), \(\bar{p} = p|p_{\text{s}}\)
- t :
-
Time (s)
- \(W\) :
-
Load capacity (N), \(\overline{W} = \left( {W| LDp_{\text{s}} } \right)\)
- \(W_{\text{r}}\) :
-
Radial load component (N), \(\overline{W}_{\text{r}} = \left( {W_{\text{r}} | LDp_{\text{s}} } \right)\)
- \(W_{\text{t}}\) :
-
Transverse load component (N), \(\overline{W}_{\text{t}} = \left( {W_{\text{t}} |LDp_{\text{s}} } \right)\)
- U :
-
Peripheral journal velocity (m/s), \(U = \omega R\)
- x :
-
Circumferential coordinate axis (m), \(x = R\theta\)
- z :
-
Axial coordinate (m), \(z = \bar{z}L\)
- \(\alpha\) :
-
Pad angle (rad)
- \(\alpha'\) :
-
Angle between central eccentricity vector and projected journal axis (rad)
- \(\delta\) :
-
Tilt angle (rad)
- \(\varepsilon ^{{\prime }}\) :
-
Dimensionless projected distance of the journal, \(\varepsilon = \left( {e^{{\prime }} /C} \right)\)
- \(\eta\) :
-
Fluid viscosity (Ns/m2)
- \(\theta ^{\prime } ,\theta\) :
-
Angular coordinates of the bearing (rad), \(\theta ^{\prime } = \left( {\theta - \left( {\alpha /2} \right)} \right)\)
- \(\varLambda \,\) :
-
Bearing number, \(\varLambda = 6\eta \omega/\left[ {p_{s} \left( {C/R} \right)^{2} } \right]\)
- \(\mu\) :
-
Friction coefficient
- \(\overline{\mu }\) :
-
Friction variable, \(\overline{\mu } = \mu (R/C)\)
- \(\phi\) :
-
Attitude angle (rad)
- \(\psi\) :
-
Assumed attitude angle (rad)
- ω :
-
Angular velocity of journal (rad/s)
References
Buske A, Rolli W (1949) Measurements of oil-film pressure in bearings under constant and variable loads. NACA Tech Note 1200:43
Dubois GB, Ocvirk FW, Mabie HH (1951) Experimental investigation of oil film pressure distribution for misaligned plain bearings. NACA Tech Note 2507
Dubois GB, Mabie HH, Ocvirk FW (1955) Experimental investigation of misaligning couples and eccentricity at ends of misaligned plain bearings. NACA Tech Note 3352
Smalley AJ, McCallion H (1966) The effect of journal misalignment on the performance of a journal bearing under steady running conditions. Proc Inst Mech Eng Conf Proc 181:45–54
Guha SK (2000) Analysis of steady-state characteristics of misaligned hydrodynamic journal bearings with isotropic roughness effect. Tribol Int 33:1–12
Bouyer J, Fillon M (2001) An experimental analysis of misalignment effects on hydrodynamic plain journal bearing performances. J Tribol 124:313–319
Krodkiewski JM, Cen Y, Sun L (1997) Improvement of stability of rotor system by introducing a hydraulic damper into an active journal bearing. Int J Rotating Mach 3:45–52
Krodkiewski JM, Sun L (1997) Modelling of multi-bearing rotor systems incorporating an active journal bearing. J Sound Vib 210:215–229
Sun L, Krodkiewski JM (2000) Experimental investigation of dynamic properties of an active journal bearing. J Sound Vib 230:1103–1117
Chasalevris A, Dohnal F (2012) A journal bearing with variable geometry for the reduction of the maximum amplitude during passage through resonance. J Vib Acoust 134:061005
Chasalevris A, Dohnal F (2015) A journal bearing with variable geometry for the suppression of vibrations in rotating shafts: Simulation, design, construction and experiment. Mech Syst Signal Process 52:506–528
Martin JK, Parkins DW (1998) Fluid film bearings. US Patent 5,772,334
Martin JK (1999) A mathematical model and numerical solution technique for a novel adjustable hydrodynamic bearing. Int J Numer Methods Fluids 30:845–864
Martin JK, Parkins DW (2001) Testing of a large adjustable hydrodynamic journal bearing. Tribol Trans 44:559–566
Martin JK (2004) Measuring the performance of a novel fluid film bearing supporting a rotor on a stationary shaft, by non-contacting means. Proc Inst Mech Eng Part K J Multi-Body Dyn 218:143–151
Shenoy BS (2008) Performance evaluation of single pad externally adjustable fluid film bearing. In: PhD thesis. Manipal University, Manipal
Shenoy BS, Pai R (2009) Theoretical investigations on the performance of an externally adjustable fluid-film bearing including misalignment and turbulence effects. Tribol Int 42:1088–1100
Shenoy BS, Pai R (2011) Dynamic characteristics of a single pad externally adjustable fluid film bearing. Ind Lubr Tribol 63:146–151
Hariharan G, Pai R (2018) Mathematical formulation of a modified film thickness equation for multipad externally adjustable fluid film bearing. Cogent Eng 5:1–15
Hargreaves DJ (1995) Predicted performance of a tri-taper journal bearing including turbulence and misalignment effects. Proc Inst Mech Eng Part J J Eng Tribol 209:85–97
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2021 Springer Nature Singapore Pte Ltd.
About this paper
Cite this paper
Hariharan, G., Srikanth Rao, D., Pai, R. (2021). Studies on the Load Carrying Capacity of a Multi-Pad Adjustable Bearing Under Misaligned Conditions. In: Rushi Kumar, B., Sivaraj, R., Prakash, J. (eds) Advances in Fluid Dynamics. Lecture Notes in Mechanical Engineering. Springer, Singapore. https://doi.org/10.1007/978-981-15-4308-1_22
Download citation
DOI: https://doi.org/10.1007/978-981-15-4308-1_22
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-15-4307-4
Online ISBN: 978-981-15-4308-1
eBook Packages: EngineeringEngineering (R0)