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1.
We considered the magnetohydrodynamic (MHD) free convective flow of an incompressible electrically conducting viscous fluid past an infinite vertical permeable porous plate with a uniform transverse magnetic field, heat source and chemical reaction in a rotating frame taking Hall current effects into account. The momentum equations for the fluid flow during absorbent medium are controlled by the Brinkman model. Through the undisturbed state, both the plate and fluid are in a rigid body rotation by the uniform angular velocity perpendicular to an infinite vertical plate. The perpendicular surface is subject to the homogeneous invariable suction at a right angle to it and the heat on the surface varies about a non-zero unvarying average whereas the warmth of complimentary flow is invariable. The systematic solutions of the velocity, temperature, and concentration distributions are acquired systematically by utilizing the perturbation method. The velocity expressions consist of steady-state and fluctuating situations. It is revealed that the steady part of the velocity field has a three-layer characteristic while the oscillatory part of the fluid field exhibits a multi-layer characteristic. The influence of various governing flow parameters on the velocity, temperature, and concentration are analyzed graphically. We also discuss computational results for the skin friction, Nusselt number, and Sherwood number in the tabular forms.  相似文献   
2.
Knowledge and Information Systems - With increasingly more people using online services, purchasing products, and reviewing them, it becomes crucial to have a system that can provide a crisp...  相似文献   
3.
ABSTRACT

In this paper, two control schemes for boost converters affected by uncertainties in input voltage and load are proposed. The boost converter dynamics is redefined in terms of new state variables to facilitate the use of a disturbance observer that can estimate matched and unmatched disturbances. A sliding surface, which is new in the context of boost converters, is proposed to enable tracking and regulation of output voltage without requiring measurement of input voltage and load current. The stability of the overall system including the disturbance observer, the sliding variable and the output is proved. The performance of the schemes is assessed for regulation of output voltage and tracking of reference voltage by simulation as well as experimentation in which various types of uncertainties and various types of reference voltages are considered.  相似文献   
4.
Mine Water and the Environment - Seepage of water through an underground coal-mine barrier is a common indicator of a potential hydrogeological hazard. The Jharia coalfield has witnessed several...  相似文献   
5.
Wireless Personal Communications - Hazard identification is an important basis for the design of coal mine safety signs. This paper analyses the coal face hazard checklists in a large state-owned...  相似文献   
6.
Journal of Failure Analysis and Prevention - The inhibition effect of Flectofenine on corrosion of mild steel in 1M HCl solution was investigated by using traditional weight loss method and...  相似文献   
7.
The present investigation is aimed at studying the deformation in thermo-microstretch elastic medium occuping the region y ? 0 with a stable internal heat source. A nonviscous fluid layer of height h is overlying the thermoelastic medium and a mechanical source of constant magnitude is applied along the fluid/solid interface. The normal mode analysis is used to obtain the exact expressions for displacement components, force stress, and temperature distribution. The numerical results are given and presented graphically for the Green–Lindsay theory of thermoelasticity. The variations of the considered variables through the horizontal distance are illustrated graphically. Comparisons are made with the results in the presence and absence of microstretch and microrotation parameters.  相似文献   
8.
9.
Multimedia Tools and Applications - By embracing Generative Adversarial Networks (GAN), several face-related applications have significantly benefited and achieved unparalleled success. Inspired by...  相似文献   
10.
Improving the performance of heat transfer fluids is altogether significant. The best approach for improving the thermal conductivity is the addition of nanoparticles to the base fluid. In the present study, specific heat, dynamic viscosity, and thermal conductivity of water-based Indian coal fly ash stable nanofluid for 0.1% to 0.5% volume concentration in the temperature range of 30 to 60°C has been investigated. To evaluate an average particle diameter of 11.5 nm, the fly ash nanoparticles were characterized with scanning electron microscopy and dynamic light scattering. Using zeta potential, the stability of nanofluid in the presence of surfactant Triton X-100 was tested. Thermal conductivity and viscosity of fly ash nanofluid increased, while specific heat decreased as volume concentration increased. The effect of temperature on the fly ash nanofluid was directly proportional to its thermal conductivity and specific heat and inversely proportional to viscosity.  相似文献   
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