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This paper presents a mathematical approach for applying the nano-scale effects on higher-order nonlocal boundary conditions for exact buckling strains of nano-beams based on a modified nonlocal Timoshenko beam theory (MNTBT) for various end conditions. Researchers usually neglect these higher-order boundary conditions in their analysis. Hence, the strain gradient approach and variational method are...
Plentiful supply of coolant might enhance the machining cost and also generates environmental hazard. As a result, substitute methods are required to eliminate the problems encountered during use of coolant. In this investigation, the impact of cutting speed, feed and lubrication conditions (dry: no lubrication, oil: machining is performed with groundnut oil and nano fluid: machining performed with...
Uncertainty is described by the cumulative distribution function (CDF). Using the CDF one describes all the main cases: the discrete case, the case when an absolutely continuous probability density exists, and the singular case, when it does not, or combinations of the three preceding cases. The reason one does not see any mention of uncertainty quantification in classical books, as Feller’s and Chung’s,...
In this study, an integrated power and refrigeration plant, based on biomass gasification, has been modeled and analyzed. The producer gas generated by gasification of solid biomass undergoes full combustion in a combustor-heat exchanger (CHX) and heats up compressed air for an indirectly heated gas turbine (GT) cycle. The waste heat of the CHX exhaust is further recovered in a recovery boiler to...
In the present study, an analytical solution based on a double perturbation method is obtained to simulate the creeping motion of a Boger drop descending in an immiscible viscoelastic quiescent medium. The perturbation parameters are considered to be the Deborah number defined based on the relaxation times of interior and exterior media and the Capillary number. The Oldroyd-B model is implemented...
The current contribution aims to address an unsteady mixed convection in stagnation point flow of an Oldroyd-B nanofluid induced due to a stretched sheet with Biot number impact. Implementation of convenient similarity transformation changes the highly nonlinear-coupled governing equations to nonlinear ordinary differential equations. Obtaining governing system has been solved for the convergent series...
In this paper, a vibro-impact gear model incorporating the influences of the lubricant and backlash is formulated. Then, a new computational algorithm validated in comparison with the “stiff” solvers, by defining a transition area and adopting the double-changed time step, is proposed to identify the influences of the lubricant on the dynamic system. The results obtained in this paper indicate that...
The objective of the present investigation is to examine the influences of radial magnetic field on the peristalsis of Eyring–Powell liquid in a curved channel. The channel walls satisfy the convective conditions of heat transfer. Problem formulation is made using conservation laws of mass, linear momentum and energy. Perturbation solutions of the resulting problems for flow and temperature through...
The most promising technology in the field of semi-active suspension systems is the use of magnetorheological property of MR fluid, whose material behavior can be controlled through external magnetic field. Devices developed based on this principle are adaptive and controllable as desired for a specific application. It is important to understand the damping characteristics of these devices before...
This work presents a comparative and descriptive study of numerical control machines solutions using Linux and Windows operating systems, used for the retrofitting of two similar models of old industrial robots, using controllers based on Computer Numerical Control (CNC). Federal University of Minas Gerais (UFMG) and University of Brasilia (UnB) adopted two different softwares, including the robot...
In this article, the boundary layer flow and heat analysis are addressed for the unsteady 3D flow of Sisko fluid over a bidirectional time-dependent stretching sheet. The governing nonlinear partial differential equations involving momentum and temperature are transformed to nonlinear ordinary differential equations while using the suitable transformations. The modeled equations are then solved numerically...
The gray relational analysis is an important technique can be effectively used for forecasting, decision making in different areas of manufacturing and products processing. In this research, the gray relational analysis has been employed to optimize the input process parameters of the developed laser-assisted jet electrochemical machine (LA-JECM) for better machining performance characteristics. Taguchi...
Currently, diesel engines are calibrated using more and more complex multiple injection strategies. Under these conditions, the characteristics of the flow exiting the fuel injector are strongly affected by the transient interaction between the needle, the sac volume and the orifices, which are not yet clear. In the current paper, a methodology combining a 1D injector model and 3D-CFD simulations...
This work studies the mechanical bending and vibration of functionally graded nanobeams using finite elements according to Euler beam theory. We implement a modified porosity model that represents porosity and Young’s modulus in an implicit form, where the density is assumed as a function of the porosity parameter, while Young’s modulus is assumed as a ratio of the mass density with porosity to that...
Parallel manipulators present high load capacity and rigidity, among other advantages, when compared to the serial manipulators. Due to their kinematic architecture, their parts are lighter. This characteristic may be an asset for designing high dynamic performance manipulators. However, parallel manipulators suffer from singularities in their workspace. This drawback can be circumvented by the use...
In order to improve the fault diagnosis accuracy of the full-hydraulic drilling rig, RS–SVM multi-sensor data fusion fault diagnosis method is proposed based on the rough set theory (RS) and support vector machine (SVM). In the method, the feature layer fusion structure is adopted and energy-normalized feature vectors of the fault signal sub-band are extracted by wavelet packet decomposition. Because...
Under the background of industry 4.0, advanced strip control process is a central part of rolling intelligent manufacturing. In the mainstream rolling control process, the work roll bending and the intermediate roll bending are turned on at the same time. Both stepwise methods and alternative methods are conducted by sacrificing adjustment ability. In this paper, the dimension of influencing factors...
An analysis is presented to report the notable features of non-Fourier’s double diffusion model in stretchable flow of modified Burgers liquid. The flow phenomenon is due to impermeable stretched sheet. The energy and mass expressions are modeled utilizing concept of non-Fourier’s double diffusion. Heat transfer mechanism is characterized within the frame of variable thermal conductivity. Relevant...
The present study has the purpose of presenting a numerical and experimental analysis of the flow patterns on the fore-body section of a sounding rocket model in the transonic regime. The measurements were carried out in the Pilot Transonic Wind Tunnel, known as TTP, at the Instituto de Aeronáutica e Espaço (IAE), in São José dos Campos, Brazil, for Mach numbers ranging from 0.6 to 1.06 and zero angle...
In the present study, the combined effect of non-uniform heat source/sink, suction/injection , thermal radiation, and viscous dissipation is investigated on the unsteady squeezing flow and heat transfer of non-Newtonian Casson fluids. By means of a suitable similarity transformation, the governing equations are converted to a set of non-linear ordinary differential equations which are solved analytically...
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