Narrow Results

The study of squeezing fluids is considered to be one of the most important areas of scientific research due to its various engineering and bioapplications such as the squeezing processes that occur in the brake mechanisms in trucks and Piston’s systems, liquid metal lubrication systems, polymer processing and compression/injection molding as well as the contraction processes in the arteries and veins. This work deals with the study of one of these applications through modeling using the basic equations governing the squeezing fluids and their boundary conditions, and the presence of some external thermal influences such as the magnetic field and linear/nonlinear thermal radiation in its basic form as a nonlinear partial differential equations system, then converting this system into nonlinear ordinary differential equations that were solved numerically and analytically for special cases. The results focused on showing the thermal and flow behavior of the fluid at different concentrations of nanoparticles, which induce the effect of thermal forces represented by the magnetic field and thermal radiation. These results were demonstrated through a set of graphs and tables and discussed in detail, and in summary, some important results were found from the physical analysis. For some of these results, the use of different types and concentrations of particles increases the viscosity of the fluid, which causes an increase in temperature ranging between 17% and 45%.

Squeezing flow of Casson liquid between two disks is a practical application in compression, polymer processing and injection molding. In this paper, the Casson liquid flow between two convectively heated disks is analyzed using Buongiorno model. Further, the heat and mass transport analysis is done by considering the impact of heat source/sink and activation energy. The continuity and momentum equations governing the unsteady two-dimensional flow are derived using conservative laws. The equations are reformulated using the similarity transformations and the reformulated equations are solved numerically with MATLAB routine bvp4c. The effect of embedding different physical parameters on the flow is analyzed through the graphs for both suction and blowing cases along with comprehensive solutions and equal Biot numbers. Results are validated with the existing literature. For both suction and blowing cases, squeezing number decreases the velocity near the lower disk but increases the velocity near the upper disk. Increasing magnetic field strength slightly increases velocity near the lower disk for equal Biot numbers.

The flow of fluid that occurs when two parallel disks are squeezed together has applications in compression, the processing of polymers, the production of plastics, injection modeling, and lubrication systems. In this paper, the unsteady squeezing flow and heat transport of nanoliquid that is subjected to convective thermal boundary conditions and viscous heating have been studied numerically. This study was inspired by the exploration of the thermophysical properties of magnetic nanoparticles in squeezing tribology. The flow between two horizontal parallel disks is accounted for where the upper disk is non-static when the lower disk is fixed. The powerful Runge–Kutta method-based shooting scheme is utilized to solve the assumed problem. The influence of pertinent key parameters on involved fields is visualized graphically and scrutinized. It is exhibited that the haphazard motion of NPs contributes highly to the enhancement of thermal and concentration fields. Also, the Robin boundary conditions affect flow fields significantly. Intensifying the Brownian motion effect enhances NPs’ concentration. Radial velocity is damped in the core region with stronger magnetic field. The mass transport rate is diminished, and the heat transmission rate is enhanced. The computations are relevant to smart nano-tribological systems in mechanical and aerospace engineering.

In this article, Magnetohydrodynamic (MHD) squeezing flow between two parallel disks is considered. The upper disk is taken to be solid and the lower one is permeable. Soret and Dufour effects are measured to explore the thermal-diffusion and diffusion-thermo effects. Governing PDEs are converted into system of ODEs with the support of suitable similarity transforms. Homotopy analysis method (HAM) has been employed to obtain the expressions for velocity, temperature and concentration profiles. Effects of different emerging parameters such as squeezing number $S$, Hartman number $M$, Prandtl number Pr, Eckert number Ec, dimensionless length $\delta$ and Schmidt number Sc on the flow are also discussed with the help of graphs for velocity, temperature and concentration. The local Nusselt and Sherwood numbers along with convergence of the series solutions are presented with the help of graphs. From the results obtained, we observed that the physical quantities like skin friction coefficient increases with increasing value of Hartmann number $M$ in the blowing case $(A<0)$ whereas a fall is observed in the suction case $(A>0)$. However, the rate of heat transfer at upper wall increases with increasing values of Dufour number Du and Soret number Sr for both the suction $(A>0)$ and blowing flow $(A<0)$, whereas, for the larger values of Dufour number Du and smaller values of Soret number Sr, a rapid fall is observed in Sherwood number Sh for both the suction $(A>0)$ and blowing $(A<0)$ cases. A numerical solution is obtained by employing Runge–Kutta method of order four (RK-4) to check the validity and reliability of the developed algorithm. A well agreement is found between both the solutions.