فهرست مطالب f. mebarek-oudina

The joint influence of variable heat source pattern and temperature-reliant viscosity on the onset of convective motion in porous bed in the presence of gravity variance have been investigated. The linear analysis is performed using normal mode analysis and the Galerkin technique is applied to analyze the impact of variable heating and changeable gravity field on the behaviour of system stability. The exponential temperature dependent viscosity is considered. We examined three different types of heat source and gravity variance function combinations: Convection is accelerated by increases in viscosity and the gravity variance parameter, but decelerated by increases in the heat source strength. It has been shown that the configuration is more stable when the gravity variance and heat source functions are combined in instance (ii), but less stable when they are combined in case (iii).

Microfluidic technology and Micro Electromechanical Systems (MEMS) have received much attention in science and engineering fields over the last few years. MEMS can be found in many areas like heat exchangers, chemical separation devices, bio-chemical analysis and micro pumps. Keeping these facts in mind, the prime purpose of the current paper is to present the flow of Carreau nanofluids through the micro-channel with the electro-osmosis, Joule heating and chemical reactions. The effect of external magnetic field is also considered into account. For the formulation of the problem, the Cartesian coordinate system is considered. The perturbed solutions have been presented by making use of regular perturbation method. The graphical results also prepared corresponding to numerous values of fluid flow phenomenon like velocity, temperature, solutal nano-particle concentration, Sherwood number and Nusselt number with different fluid variables. It is concluded from our analysis that; velocity decrement is identified with respect to the enhancing the magnetic parameter (Hartmann number). The Schmidt number, Radiation term, Prandtl number and chemical reaction term increase the solutal nano-particle concentration. The outcomes of the Newtonian liquid model can be obtained from our scrutiny. The present scrutiny has many applications in engineering sciences such as electromagnetic micro pumps and nano-mechanics.

In this examination, a sensitivity analysis is implemented using response surface strategies to control the Walters-B nanofluid stagnant point flow caused by a Riga surface. An electromagnetic actuator is known as Riga-surface. The Buongiorno model is used to construct the mathematical model, which includes a Newtonian heating condition as well as radiation effects. Via the fundamental laws of mass, momentum, and energy, transformation is incorporated to obtain nonlinear ordinary differential equations. To solve the governing system, the numerical shooting approach along with Runge-Kutta scheme is used to solve the governing system. A comparison with existing research is made, and the results are obtained to be in strong agreement. Focusing on the response of local Nusselt number to variation of input variables, an experimental structure is incorporated by sensitivity analysis. As underline, the LNN is quite sensitive to radiation number rather than other parameters of interest. Meanwhile, it is demonstrated that sensitivity of LNN to Brownian number decreases with growing thermophoresis number but sensitivity value is also vary from positive to negative for all values of Brownian number. The results are assumed to provide a tentative guidance for possible lab-based experiments.