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The purpose of this study is a numerical analysis of steady-state heat transfer behavior of couple-stress nanofluid sandwiched between viscous fluids. It should be noted that this research deals with the development of a cooling system for the electronic devices.

Stokes model is used to define the couple-stress fluid and the single-phase nanofluid model is used to define the nanofluid transport processes. The fluids in all regions are assumed to be incompressible, immiscible and the transport properties in all the three layers are assumed to be constant. The governing coupled linear ordinary differential equations are made dimensionless by using appropriate fundamental quantities. The exact solutions obtained for the velocity and temperature fields are evaluated numerically for various model parameters.

The results are demonstrated using different types of nanoparticles such as copper, silver, silicon oxide (SiO₂), titanium oxide (TiO₂) and diamond. The investigations are carried out using copper–water nanofluid for different values of couple-stress parameter a with a range of 0 = a = 12, solid volume fraction ϕ with a range of 0.0 ≤ ϕ ≤ 0.05, Eckert number Ec with a range of 0.001 ≤ Ec ≤ 6 and Prandtl number Pr with a range of 0.001 ≤ Pr ≤ 6. It was found that the Nusselt number increases by increasing the couple stress parameter, Eckert number and Prandtl number and it decreases with a growth of the solid volume fraction parameter. It was also observed that using SiO₂–water nanofluid, the optimal Nusselt number is obtained. Further, using copper, silver, diamond and TiO₂, nanoparticles and water as a base fluid does not show any significant changes in the rate of heat transfer. The couple-stress parameter enhances the velocity and temperature fields whereas the solid volume fraction suppresses the flow field for both Newtonian and couple-stress fluid.

The originality of this work is to analyze the heat transfer behavior of couple-stress nanofluid sandwiched between viscous fluids. The results would benefit scientists and engineers to become familiar with the analysis of convective heat transfer and flow structures in nanofluids and the way to predict the heat transfer rate in advanced technical systems, in industrial sectors including transportation, power generation, chemical sectors, electronics, etc.

The purpose of this paper is to present the effect of the preload on the static characteristics of three-lobe bearings lubricated with a fluid blended with high polymer additives modeled as a couple stress fluid.

Based on the micro-continuum theory, the modified Reynolds equation for couple stress fluids is solved using a finite difference method to obtain the distribution of the pressure, the load-carrying capacity, the attitude angle, the friction coefficient and the side leakage for various values of the couple stress parameter and the preload factor.

The results show that the presence of a couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. Thus, it is found that the preload significantly affects the performance of the three-lobe journal bearing lubricated with a couple stress fluid or a Newtonian fluid. Moreover, the investigation showed that increasing the preload factor exhibits an increase in the load carrying capacity and the attitude angle, but it decreases the friction coefficient and the side leakage especially at a lower preload factor. Furthermore, using a couple stress fluid and a higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient.

This study helped improve the performance characteristics of the three-lobe journal bearing.

The presence of couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. The usage of the couple stress fluid and the higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient.

A theoretical study of the combined effects of non‐Newtonian couple stresses and fluid inertia forces on the squeeze‐film behaviors for parallel circular plates is presented in this paper. Based upon the micro‐continuum theory, the Stokes constitutive equations are used to account for the couple stress effects resulting from the lubricant blended with various additives. The convective inertia forces included in the momentum equation are approximated by the mean value averaged across the fluid film thickness. Numerical solutions for the squeezing film characteristics are presented for various values of couple stress parameter and Reynolds number. Comparing with the classical Newtonian non‐inertia flow, the combined effects of couple stresses and convective inertia forces result in a larger load‐carrying capacity and therefore, increase the response time of the squeezing film plates.

This paper presents an analysis of the static characteristics of two-lobe journal bearings lubricated with couple stress fluids operating in a turbulent regime. The modified Reynolds equation for a couple stress fluids taking into consideration the effect of turbulence is solved using finite difference method. The load-carrying capacity, attitude angle, friction coefficient and side leakage are determined for various values of the couple stress parameter and Reynolds number. It is found that the couple stress fluids affect significantly on the performance of a two-lobe journal bearing in laminar and turbulent regime.

The modified Reynolds equation for a couple stress fluids taking into consideration the effect of turbulence is solved using finite difference method.

It is found that the couple stress fluids affect significantly on the performance of a two-lobe journal bearing in laminar and turbulent regime.

A couple stress fluid is used for lubrication of a two-lobe journal bearing in turbulent regime and laminar.

The purpose of this paper is to examine the recursive perspective that emphasizes bureaucracy as a source of officers’ stress, explain officers’ stress as a loosely coupled effect, examine the positive effects of loose coupling and legitimize the necessity of improving context management as a stress-reduction factor.

The research methodology uses a quantitative perspective; the members of two police forces constituted the universe; the sampling technique was not random and accidental; and an exploratory factor analysis and an invariance measure were performed.

The stress phenomenon is common and similar in both police forces, which means that it is indifferent to their organizational differences and has common causes. Loose coupling is present in both police work settings and entails significant stress; and the search for an explanation of the stress caused by loosely coupled elements should focus on both the value chain and the processes.

Addressing this phenomenon should entail a twofold improvement strategy: the correction of loosely coupled organizational factors by revising the management processes that cause stress and the prevention of loosely coupled effects by using professional training to enhance adaptive behavior within specific contexts.

Police organizations are addressed as loosely coupled (anarchic organized) systems instead of tightly coupled (bureaucratic) systems. The loosely coupled factors that emerge inside bureaucratic organizations cause significant stress among officers and complementary research is necessary to analyze the fallacious nature of the recursive attribution of police stress to bureaucratic characteristics.

The purpose of the present study is to provide the dynamic characteristics of long journal bearings lubricated with couple stress fluids.

Based upon the micro‐continuum theory generated by Stokes, the dynamic Reynolds‐type equation governing the film pressure is derived to account for the couple stress effects resulting from the non‐Newtonian behavior of complex fluids. By applying the linear stability theory to the non‐linear equations of motion the journal rotor, the equilibrium positions and dynamic characteristics of the system are evaluated.

As compared to the classical Newtonian model, the effects of couple stresses signify enhanced stiffness and damping coefficients (including K_XX, K_XY , B_XX and B_XY) at moderate values of the steady eccentricity ratio. Totally, as the rotor center operates at an eccentricity ratio about ε_s≤0.71, long bearings lubricated with couple stress fluids under small disturbance results in a higher stability threshold speed than that of the Newtonian‐lubricant case.

These findings provide engineers useful information in designing journal‐bearing systems.

The purpose of this paper is to investigate the two-dimensional axisymmetric problem in a homogeneous, isotropic modified couple stress thermoelastic diffusion (TD) medium in the context of dual-phase-lag model.

The Laplace and Hankel transforms have been applied to find the general solution to the field equations. The components of displacement, stresses, temperature change and chemical potential are obtained in the transformed domain. The resulting quantities are obtained in the physical domain by using numerical inversion technique.

The components of normal stress, tangential stress, tangential couple stress, temperature change and chemical potential are obtained numerically and depicted graphically to see the effect of dual-phase-lag diffusion (DLD), dual-phase-lag heat transfer (DLT) and TD models in the absence and presence of couple stress parameter.

Comparisons are made in the absence and presence of couple stress DLD, DLT and TD models.

The purpose of this paper is to investigate the thermoelastic functionally graded beam in a modified couple stress theory subjected to a dual-phase-lag model.

The governing equations are solved by using the Euler-Bernoulli beam assumption and the Laplace transform technique. The lateral deflection, temperature change, displacement component, axial stress and thermal moment of the beam are obtained by ramp type heating in the transformed domain. A general algorithm of the inverse Laplace transform is developed to recover the results in a physical domain.

The lateral deflection, temperature change, displacement component, axial stress and thermal moment of the beam are computed numerically and presented graphically to show the effect of ramp time parameter and phase lags of heating.

Comparisons are made in the absence and presence of coupled dual-phase-lag thermoelastic and coupled thermoelastic L-S theories and also different values of ramp type parameter.

The purpose of this paper is to investigate the two-dimensional problem in couple stress thermoelastic medium for a half space is established and state space approach has been applied to solve the problem.

Normal mode analysis is used to obtain the exact expressions for normal stress, tangential stress and couple stress. Numerical calculation is prepared for these quantities and depicted graphically for a special model.

The expressions for normal stress, tangential stress and couple stress are obtained numerically and depicted graphically to see the couple stress effect.

It is found that couple stress effect decrease the value of normal stress components for circular frequency equal to 0.5 for small values of the wave number and then increases whereas the values of normal stress components decrease first and then increase monotonically for circular frequency equal to 0.1 when the force is applied in normal direction and the values of tangential stress components and couple stress components decrease for all values of wave number. But the values for normal stress components, tangential stress components and couple stress components increase when the force is applied in tangential direction.

The purpose of this paper is to examine the moderating role of marital status between infidelity and development of stress, anxiety and depression. Additionally, to investigate the relationship among infidelity, stress, anxiety and depression among married couples and divorced individual.

A purposive sampling technique was used based on cross-sectional design. In total, 200 participants (married couples, n=100; divorced individuals, n=100) were incorporated from different NGO’s and welfare organizations of Rawalpindi, and Islamabad, Pakistan. Age ranged from 20 to 60 years. Two scales were used to measure the infidelity, stress, anxiety and depression in married couples and divorced couples.

The result revealed that emotional infidelity was positively significant correlated with stress (r=0.39, p=0.001), anxiety (r=0.40, p=0.001) and depression (r=0.35, p=0.001) for married couples. The result also displayed that sexual infidelity was positively significant correlated with stress (r=0.39, p=0.001), anxiety (r=0.39, p=0.001) and depression (r=0.34, p=0.001) for married couples. The result further elaborated that emotional infidelity and sexual infidelities were positively non-significant correlated with stress, anxiety and depression for divorced individuals. The analysis results revealed that marital status was moderator between infidelity and development of stress, anxiety and depression.

This paper consisted of sample from three basic cities of Pakistan; thus, this paper finding may not be applied on whole population. Consequently, explanatory, exploratory and descriptive studies would be useful to enlighten the infidelity’s mechanism in prolongation of psychological distress across married couples and divorced individual in detail. Local tools to measure gender-related issues would be helpful in prospect while it combine cultural aspects as well.

This study would be helpful in clinical settings to raise the awareness to effectively deal with their children.

The study recommended that those divorced individuals who had experienced either sexual infidelity or emotional infidelity were more likely to develop psychological problems as compared to married couples. This study would be helpful in clinical settings to raise the awareness to effectively deal with their children.