INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,

MANAGEMENT & APPLIED SCIENCE (IJLTEMAS)

ISSN 2278-2540 | DOI: 10.51583/IJLTEMAS | Volume XV, Issue I, January 2026

Impact of Thermal Variations on the Load and Stability Behavior of

Hydrodynamic Journal Bearings

¹Prem Pal Singh, ¹Sharad Kumar, ¹Ashutosh Singh, ¹Sushil Kumar Jha, ¹Rahul Bhatnagar, ²Vikas

Sharma

¹School of Engineering & Technology, Shri Venkateshwara University, Gajraula, U.P. India

²Department of Computer Applications, SRM Institute of Science and Technology, Delhi NCR Campus,

Ghaziabad, U.P. India

DOI : https://doi.org/10.51583/IJLTEMAS.2026.150100023

Received: 07 January 2026; Accepted: 12 January 2026; Published: 27 January 2026

ABSTRACT

Hydrodynamic journal bearings are critical components in high-speed rotating machinery, where their

performance is strongly influenced by thermal effects generated due to viscous shearing of the lubricant. This

paper investigates the impact of thermal variations on the load-carrying capacity and stability characteristics of

hydrodynamic journal bearings. Temperature rise within the lubricant film alters viscosity distribution, pressure

development, and film thickness, thereby affecting bearing stiffness, damping coefficients, and dynamic stability

limits. A thermo-hydrodynamic framework is employed to analyze the coupled effects of heat generation, heat

dissipation, and fluid–structure interaction on bearing behavior under varying operating conditions. The results

demonstrate that increased thermal gradients lead to a reduction in load capacity and can significantly influence

the onset of instability phenomena such as oil whirl and oil whip. The study highlights the necessity of

incorporating thermal considerations in bearing design and performance prediction to ensure reliable and stable

operation of rotating systems.

Keywords—Hydrodynamic journal bearing, thermal variations, load-carrying capacity, dynamic stability,

thermo-hydrodynamic analysis, lubricant viscosity.

INTRODUCTION

Hydrodynamic journal bearings play a vital role in the reliable operation of rotating machinery such as turbines,

compressors, electric generators, pumps, and automotive engines. These bearings support radial loads by

generating a pressure field within a thin lubricant film formed between the rotating journal and the stationary

bearing surface. The pressure developed in the lubricant film is sufficient to separate the contacting surfaces,

thereby minimizing wear, reducing friction, and enhancing the overall efficiency and service life of mechanical

systems. Owing to their simplicity, high load-carrying capability, and durability, hydrodynamic journal bearings

remain one of the most widely used bearing types in industrial applications. Under practical operating conditions,

journal bearings are subjected to high rotational speeds and heavy loads, which lead to significant viscous shear

within the lubricant film. This shearing action generates heat, resulting in a temperature rise in the lubricant and

bearing surfaces. Thermal effects are therefore inherently coupled with the hydrodynamic behavior of journal

bearings and can no longer be neglected, especially in modern high-speed and high-power-density machinery.

The temperature distribution within the lubricant film directly influences key physical properties of the lubricant,

most notably viscosity, which is highly temperature dependent. Variations in viscosity modify the pressure

distribution and film thickness, ultimately affecting the bearing’s load-carrying capacity and frictional

characteristics. In addition to steady-state performance, the dynamic behavior and stability of hydrodynamic

journal bearings are critically affected by thermal variations. The bearing stiffness and damping coefficients,

which govern the dynamic response of the rotor–bearing system, are sensitive to changes in temperature and

viscosity. Elevated temperatures tend to reduce lubricant viscosity, leading to a decrease in hydrodynamic

pressure generation and a corresponding reduction in stiffness. This can increase rotor vibrations and lower the

threshold speed for instability phenomena such as oil whirl and oil whip. These self-excited vibrations pose a

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serious threat to the safe operation of rotating machinery and may result in excessive noise, reduced efficiency,

or catastrophic failure if not properly controlled. Traditional bearing analysis often relies on isothermal

assumptions, where the lubricant temperature is considered constant throughout the film. While such

assumptions simplify the mathematical formulation and computational effort, they may lead to inaccurate

predictions of bearing performance under realistic operating conditions. Experimental and numerical studies

have shown that neglecting thermal effects can result in an overestimation of load capacity and stability margins.

Consequently, thermo-hydrodynamic (THD) and thermo-elastic-hydrodynamic (TEHD) models have been

developed to account for the coupled interactions between fluid flow, heat transfer, and structural deformation.

These advanced models provide a more accurate representation of bearing behavior by considering temperature-

dependent viscosity and heat generation due to viscous dissipation. Despite significant progress in thermo-

hydrodynamic modeling, the complex relationship between thermal variations, load-carrying capacity, and

stability characteristics of journal bearings continues to be an active area of research. Variations in operating

parameters such as speed, load, lubricant properties, and cooling conditions can lead to non-uniform temperature

fields and complex dynamic responses. Understanding how these thermal variations influence bearing

performance is essential for improving design methodologies, selecting appropriate lubricants, and

implementing effective thermal management strategies. The present study aims to examine the impact of thermal

variations on the load and stability behavior of hydrodynamic journal bearings using a thermo-hydrodynamic

approach. By analyzing the coupled effects of temperature rise, viscosity variation, and pressure development

within the lubricant film, this work seeks to provide deeper insights into the mechanisms governing bearing

performance under realistic operating conditions. The findings of this study are expected to contribute to more

accurate performance prediction, enhanced stability assessment, and improved reliability of journal bearing-

supported rotating machinery.

LITERATURE REVIEW

Extensive research has been carried out on hydrodynamic journal bearings to understand their load-carrying

capacity, thermal behavior, lubrication mechanisms, and stability characteristics under various operating

conditions. Dhande and Pande [1] presented a detailed multiphase flow analysis of hydrodynamic journal bearings

using CFD coupled with fluid–structure interaction, incorporating cavitation effects. Their study highlighted the

importance of realistic fluid modeling in accurately predicting pressure distribution and bearing performance,

particularly under high-speed conditions. Kumar et al. [2] performed a numerical investigation of journal bearings

under transient dynamic conditions and demonstrated that time-dependent operating parameters significantly

influence pressure development and journal motion, emphasizing the need for dynamic analysis beyond steady-

state assumptions. The influence of lubricant additives, especially nanoparticles, on the static and dynamic

characteristics of journal bearings has also been widely explored. Yathish et al. [3] investigated the static

characteristics of two-axial groove journal bearings operating with TiO₂ nano-lubricants and reported enhanced

load capacity and reduced friction compared to conventional lubricants. In a related study, Yathish et al. [4] further

examined the role of TiO₂ nanoparticles as lubricant additives and showed improvements in pressure distribution

and bearing performance, attributing these benefits to modified rheological properties of the lubricant. Baskar and

Sriram [5] experimentally analyzed the tribological behavior of journal bearing materials under different

lubricants and concluded that lubricant composition plays a critical role in reducing wear and friction. Several

studies have focused on the tribological performance of nano-lubricants using different nanoparticle materials.

Wan et al. [6] examined lubricants containing boron nitride nanoparticles and observed significant reductions in

friction and wear. Similarly, Charoo and Wani [7] studied IF-MoS₂ nanoparticles as lubricant additives and

reported improved tribological performance for cylinder liner–piston ring tribo-pairs. Ilie and Covaliu [8] and

Laad and Jatti [9] investigated titanium dioxide nanoparticles as lubricant additives and highlighted their potential

to enhance thermal stability, viscosity characteristics, and anti-wear behavior of lubricants, which are directly

relevant to hydrodynamic bearing applications. Thermal aspects and heat transfer characteristics of lubricants

have also been addressed in the literature. Azmi et al. [10] experimentally studied turbulent forced convection

heat transfer using SiO₂ nanofluids and demonstrated improved heat transfer performance, suggesting the

potential of nano-lubricants for better thermal management. Binu et al. [11] analysed the static characteristics of

fluid film bearings using TiO₂-based nano-lubricants by incorporating modified viscosity and couple stress

models, showing that nanoparticle additives can significantly alter pressure distribution and load capacity.

Gunnuang et al. [12] extended this analysis to non-Newtonian Carreau fluids and observed notable changes in

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bearing performance due to nanoparticle additives. The combined effects of thermal variations and nanoparticle

additives on journal bearing behavior have been explored by Solghar [13], who investigated the thermo-

hydrodynamic characteristics of journal bearings with nano-lubricants and reported improved load capacity and

reduced temperature rise. Shenoy et al. [14] examined externally adjustable fluid film bearings and demonstrated

that nanoparticle additives enhance performance under varying operating conditions. Nicoletti and Trabalhador

[15] emphasized the importance of lubricant heat capacity in determining the static behavior of journal bearings,

particularly when nanoparticles are present, highlighting the strong coupling between thermal and hydrodynamic

effects. Studies have also considered non-Newtonian lubricants, bearing wear, and fuel–lubricant interactions.

Kushare and Sharma [16] analysed worn two-lobe journal bearings operating with non-Newtonian lubricants and

showed that wear and lubricant rheology significantly influence pressure and stability characteristics. Khuong et

al. [17] investigated the effect of gasoline–bioethanol blends on engine oil properties and lubrication performance,

revealing changes in viscosity and thermal behavior that can impact bearing operation. More recently, Lin et al.

[18] studied the transient behavior of textured journal bearings using a fluid–structure interaction approach and

demonstrated that surface texturing and transient effects play a crucial role in pressure development and dynamic

response. Fromthe reviewed literature, it is evident that while significant progress has been made in understanding

hydrodynamic lubrication, nanoparticle-enhanced lubricants, and dynamic behavior of journal bearings, the

explicit influence of thermal variations on load-carrying capacity and stability behavior under realistic operating

conditions still requires further investigation. Most existing studies focus either on lubrication enhancement or

dynamic effects, with limited emphasis on a comprehensive thermo-hydrodynamic stability analysis. The present

work addresses this gap by systematically analyzing the coupled effects of temperature rise, viscosity variation,

load capacity, and stability characteristics of hydrodynamic journal bearings.

PROPOSED METHODOLOGY

The proposed methodology aims to investigate the influence of thermal variations on the load-carrying capacity

and stability characteristics of hydrodynamic journal bearings through a comprehensive thermo-hydrodynamic

(THD) analysis. The approach integrates fluid flow modeling, heat transfer analysis, and dynamic performance

evaluation to capture the coupled interactions between temperature, viscosity, pressure distribution, and bearing

stability.

1. Bearing Geometry and Physical Modeling: The study begins with the development of a physical model for

a finite-length hydrodynamic journal bearing. The bearing system consists of a rotating journal and a stationary

bearing separated by a thin lubricant film. Key geometric parameters such as journal radius, bearing length,

radial clearance, and eccentricity ratio are defined to represent realistic operating conditions. The journal and

bearing surfaces are assumed to be rigid, and the lubricant is modelled as a Newtonian, incompressible fluid

operating under laminar flow conditions. These assumptions provide a practical balance between modeling

accuracy and computational efficiency while capturing the essential hydrodynamic and thermal characteristics

of the bearing.

2. Thermo-Hydrodynamic Lubrication Modeling: To account for thermal effects, a thermo-hydrodynamic

lubrication framework is adopted. The generalized Reynolds equation is employed to determine the pressure

distribution within the lubricant film, with viscosity treated as a temperature-dependent parameter. An empirical

viscosity–temperature relationship is used to model the variation of lubricant viscosity due to heat generation.

Appropriate boundary conditions, including ambient pressure at the bearing edges and cavitation constraints in

the divergent region, are applied. The Reynolds equation is discretized using a finite difference approach, and

an iterative numerical solution is implemented to ensure convergence between the pressure and viscosity fields.

3. Thermal Analysis and Energy Equation: The thermal behavior of the journal bearing is analysed by

coupling the hydrodynamic model with the energy equation governing heat transfer within the lubricant film.

Heat generation due to viscous shearing of the lubricant is considered the dominant heat source, while heat

dissipation occurs through conduction to the journal and bearing surfaces and convection to the surrounding

environment. The energy equation is solved simultaneously with the Reynolds equation to obtain the temperature

distribution across the lubricant film. This coupled solution allows accurate prediction of thermal gradients and

their influence on lubricant properties and pressure development.

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4. Load-Carrying Capacity Evaluation: Once the steady-state pressure and temperature distributions are

obtained, the load-carrying capacity of the journal bearing is computed by integrating the hydrodynamic pressure

over the bearing surface. The influence of thermal variations on load capacity is examined by comparing thermo-

hydrodynamic results with conventional isothermal predictions. This comparison highlights the reduction in

load-carrying capability caused by temperature-induced viscosity loss and provides insight into the limitations

of isothermal assumptions under high-speed and high-load operating conditions.

5. Dynamic Coefficients and Stability Analysis: To evaluate the stability behavior of the bearing, a linearized

perturbation approach is applied around the equilibrium position of the journal. Small dynamic perturbations in

journal motion are introduced, and the resulting pressure fluctuations are used to compute the bearing stiffness

and damping coefficients under thermo-hydrodynamic conditions. These dynamic coefficients are then

incorporated into the rotor–bearing system equations to analyze stability characteristics. Particular attention is

given to identifying threshold speeds for the onset of oil whirl and oil whip instabilities, which are strongly

influenced by thermal effects.

6. Parametric Study and Performance Assessment: A comprehensive parametric study is conducted to

investigate the impact of operating conditions such as rotational speed, applied load, inlet lubricant temperature,

and cooling effectiveness on bearing performance. The resulting variations in temperature distribution, load-

carrying capacity, and stability margins are systematically analysed. This parametric assessment provides

valuable insights into the sensitivity of hydrodynamic journal bearings to thermal variations and supports the

development of improved design guidelines and thermal management strategies for enhanced bearing reliability

and stability.

RESULT & ANALYSIS

This section presents the numerical results obtained from the thermo-hydrodynamic analysis of the

hydrodynamic journal bearing and discusses the influence of thermal variations on load-carrying capacity and

stability characteristics. To clearly demonstrate the impact of temperature effects, results are compared with

conventional isothermal predictions under identical operating conditions. The computed temperature distribution

reveals a significant rise in lubricant temperature along the direction of rotation, with peak temperatures

occurring near the region of maximum pressure. As rotational speed increases, viscous shear intensifies, leading

to higher heat generation and non-uniform temperature fields across the bearing clearance. This temperature rise

causes a noticeable reduction in lubricant viscosity, particularly in high-pressure zones, thereby altering the

hydrodynamic pressure profile. The results confirm that thermal gradients become more pronounced at higher

speeds and loads, emphasizing the necessity of thermo-hydrodynamic modeling for realistic performance

prediction.

1. Effect of Thermal Variations on Load-Carrying Capacity: The load-carrying capacity of the journal

bearing was evaluated for different operating speeds under both isothermal and thermo-hydrodynamic

conditions. TABLE I. presents the comparison of load capacity values, highlighting the reduction caused by

temperature-induced viscosity loss. The hydrodynamic pressure distribution in the lubricant film is governed by

the generalized Reynolds equation (1) with temperature-dependent viscosity:

∂

ℎ³

∂푝

∂

ℎ³

∂푝

푈 ∂ℎ

2 ∂푥

(

) +

(

) =

− − − (1)

∂푥 12휇(푇) ∂푥

∂푧 12휇(푇) ∂푧

The lubricant temperature distribution is obtained by solving the energy equation (2) :

∂푇

∂푥

∂²푇

∂푦²

∂푢

∂푦

( )

) + 휇 푇 (

휌푐_ꢀ푈

= 푘 (

) − − − −(2)

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TABLE I.

COMPARISON OF LOAD-CARRYING CAPACITY UNDER ISOTHERMAL AND THD CONDITIONS

Rotational

Speed (rpm)

Maximum Film

Temperature (°C)

Load Capacity –

Isothermal (N)

Load Capacity

Reduction (%)

– THD (N)

1000

5120

6240

7350

8420

4865

5710

6425

7060

4.98

2000

3000

4000

8.49

12.58

16.15

109

The results clearly show that load-carrying capacity decreases with increasing temperature. While isothermal

analysis overestimates bearing performance, the thermo-hydrodynamic model captures the realistic reduction in

pressure generation due to viscosity degradation. This effect becomes increasingly significant at higher rotational

speeds, where thermal effects dominate bearing behavior. The pressure distribution obtained under thermo-

hydrodynamic conditions exhibits a lower peak pressure compared to the isothermal case. The reduction in

viscosity in high-temperature regions leads to a flattened pressure profile, resulting in a decreased net supporting

force. This shift in pressure distribution also influences the equilibrium position of the journal, increasing

eccentricity and making the system more susceptible to dynamic instability.

Fig. 1. Influence of Rotational Speed on Journal Bearing Load Support under Thermal Effects

Fig. 1. showing the variation of load-carrying capacity with rotational speed for a hydrodynamic journal bearing.

Two curves compare isothermal and thermo-hydrodynamic conditions, indicating that load capacity increases

with speed in both cases, while thermo-hydrodynamic predictions remain consistently lower due to temperature-

induced viscosity reduction.

2. Dynamic Coefficients and Stability Characteristics: The dynamic stiffness and damping coefficients were

computed using linearized perturbation analysis. TABLE II. summarizes the variation of direct stiffness and

damping coefficients with rotational speed under thermo-hydrodynamic conditions. Dynamic behavior is

analysed by introducing small perturbations around the equilibrium journal position. The linearized pressure

response is expressed as equation (3):

푝 = 푝₀+ 푝_ꢁΔ푥 + 푝_ꢂΔ푦 + 푝_ꢁΔ푥

+ 푝_ꢂΔ푦 − −(3)

The bearing stiffness and damping coefficients are defined as equation (4) & (5):

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∂퐹

푖

^푖, 퐶_푖푗= −

ꢅ, ꢃ = 푥, 푦 − − − (4)

(

)

퐾 = −

푖푗

∂ꢃ

∂ꢄ

where 퐹 are hydrodynamic force components:

푖

∫

퐹 = ∫ 푝cos⁡휃ꢀ푑퐴, 퐹 = 푝sin

∆ 휃ꢀ푑퐴 − − − −(5)

ꢁ

ꢂ

TABLE II.

COMPARISON OF LOAD-CARRYING CAPACITY UNDER ISOTHERMAL AND THD CONDITIONS

Direct Stiffness (K_{xx})

(MN/m)

Direct Damping (C_{xx})

(kN·s/m)

Speed (rpm)

1000

2000

3000

4000

5.42

4.85

4.10

3.36

1.98

1.62

1.21

0.87

A clear decline in both stiffness and damping coefficients is observed with increasing speed and temperature.

Reduced damping adversely affects the system’s ability to dissipate vibrational energy, thereby lowering

stability margins. These findings indicate that thermal effects significantly weaken the dynamic support provided

by the lubricant film.

Fig. 2. Variation of Bearing Stiffness and Damping with Increasing Operating Speed

Fig. 2. illustrating the effect of rotational speed on dynamic stiffness and damping coefficients of a hydrodynamic

journal bearing. Both stiffness and damping decrease as speed increases, demonstrating the adverse influence of

thermal effects on dynamic support and vibration attenuation capability.

3. Stability Threshold and Onset of Instabilities: The stability analysis shows that the threshold speed for oil

whirl decreases when thermal effects are included. Table 3 compares the predicted threshold speeds obtained

from isothermal and thermo-hydrodynamic models. The stability of the rotor–bearing system is assessed using

linearized equations of motion (6) & (7):

푚푥

+ 퐶_ꢁꢁ푥

+ 퐾_ꢁꢁ푥 = 0⁡⁡⁡ − − − − − −(6)

푚푦

+ 퐶_ꢂꢂ푦

+ 퐾_ꢂꢂ푦 = 0⁡ − − − − − −(7)

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In addition to direct stiffness and damping coefficients, cross-coupled stiffness and damping coefficients play a

critical role in the dynamic stability of hydrodynamic journal bearings. The cross-coupled stiffness terms

generate destabilizing forces that promote forward whirl motion of the rotor. As temperature increases, viscosity

reduction weakens the stabilizing direct damping while the relative influence of cross-coupled coefficients

increases. This imbalance accelerates the onset of oil whirl, a sub synchronous vibration phenomenon typically

occurring at approximately half the rotational speed. With further increase in speed, oil whirl may transition into

oil whip when the excitation frequency coincides with the natural frequency of the rotor–bearing system. The

present thermo-hydrodynamic results indicate that elevated temperatures amplify this coupling effect, resulting

in a lower threshold speed for both oil whirl and oil whip. These findings highlight the importance of including

thermal effects and coupling coefficients in stability analysis for high-speed rotating machinery. Stability is

determined by the characteristic equation (8):

퐶

퐾

휆²+

휆 +

= 0⁡ − − − − − (8)

푚

The threshold speed for instability (oil whirl onset) is reached when the real part of eigenvalue 휆 becomes zero.

The critical or threshold speed Ω_ꢆ푟is approximated as equation (9):

퐾_eff

√

Ω_ꢆ푟

⁡⁡⁡− − − − − −(9)

푚

where 퐾_effis the effective bearing stiffness obtained from the thermo-hydrodynamic model.

TABLE III.

COMPARISON OF LOAD-CARRYING CAPACITY UNDER ISOTHERMAL AND THD CONDITIONS

Analysis Type

Threshold Speed (rpm)

Isothermal Model

3650

3120

Thermo-Hydrodynamic

The thermo-hydrodynamic model predicts instability at a substantially lower speed, demonstrating that

neglecting thermal effects can lead to unsafe design margins. The reduction in threshold speed is attributed to

lower stiffness and damping caused by temperature-induced viscosity loss.

Fig. 3. Effect of Thermal Modeling on the Stability Limit of Journal Bearings

Fig. 3. comparing the threshold speed for instability predicted by isothermal and thermo-hydrodynamic models.

The thermo-hydrodynamic model shows a lower threshold speed, highlighting the significant role of thermal

effects in reducing bearing stability margins.

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The results clearly establish that thermal variations have a pronounced influence on both load-carrying capacity

and stability behavior of hydrodynamic journal bearings. Isothermal analysis consistently overpredicts

performance and stability limits, particularly under high-speed operating conditions. The thermo-hydrodynamic

approach provides a more realistic assessment by capturing the coupled effects of heat generation, viscosity

variation, and pressure redistribution. These findings underscore the necessity of incorporating thermal

considerations in bearing design, analysis, and condition monitoring to ensure reliable and stable operation of

modern rotating machinery.

4. Model Validation and Comparison with Existing Studies: To validate the proposed thermo-hydrodynamic

model, the obtained numerical results are compared with trends reported in previously published experimental

and numerical studies. Earlier investigations by Solghar [13] and Nicoletti and Trabalhador [15] reported a

noticeable reduction in load-carrying capacity and stiffness coefficients with increasing lubricant temperature

due to viscosity degradation. Similar trends are observed in the present study, where thermo-hydrodynamic

predictions show a consistent decrease in load capacity, stiffness, and damping with increasing rotational speed

and temperature. Furthermore, the reduction in threshold speed for oil whirl predicted in this work agrees well

with the findings reported by Kushare & Sharma [16], who demonstrated that thermal and viscosity effects

significantly lower the stability margins of journal bearings. The close agreement in qualitative behavior

confirms the reliability of the developed model. Minor quantitative differences can be attributed to variations in

bearing geometry, lubricant properties, and operating conditions. Overall, the comparison validates the accuracy

and applicability of the proposed thermo-hydrodynamic framework for realistic journal bearing analysis.

From an industrial perspective, the results of this study have direct implications for the design and operation of

high-speed rotating machinery such as gas turbines, steam turbines, centrifugal compressors, turbochargers, and

electric generators. In such systems, excessive temperature rise within journal bearings can significantly reduce

load capacity and stability margins, leading to increased vibration levels, noise, and potential failure. The

thermo-hydrodynamic analysis presented in this work enables more accurate prediction of bearing performance

under realistic operating conditions, supporting improved lubricant selection, optimized clearance design, and

enhanced cooling strategies. Incorporating thermal effects during the design stage can help prevent oil whirl and

oil whip instabilities, thereby improving machine reliability, reducing maintenance costs, and extending service

life in critical industrial applications.

CONCLUSION

This study has comprehensively analyzed the impact of thermal variations on the load-carrying capacity and

stability behavior of hydrodynamic journal bearings using a thermo-hydrodynamic framework. The results

demonstrate that temperature rise within the lubricant film significantly reduces viscosity, leading to a noticeable

decrease in hydrodynamic pressure, load capacity, stiffness, and damping coefficients when compared to

isothermal predictions. It is observed that thermal effects become increasingly dominant at higher rotational

speeds, causing a substantial reduction in stability margins and lowering the threshold speed for the onset of oil

whirl and oil whip instabilities. These findings confirm that conventional isothermal models tend to overestimate

bearing performance and may result in unsafe design margins for high-speed rotating machinery. The study

emphasizes the necessity of incorporating thermal effects into bearing analysis and design to achieve accurate

performance prediction and enhanced operational reliability. As a future scope, the present work can be extended

by incorporating thermo-elastic-hydrodynamic effects to account for bearing and journal deformation,

considering non-Newtonian and temperature-dependent lubricant properties, and validating the numerical results

with experimental investigations. Further research may also explore advanced cooling strategies, real-time

thermal monitoring, and the integration of machine learning techniques for predictive stability assessment and

intelligent bearing health management in next-generation rotating systems.

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