Journal of Modern Processes in Manufacturing and Production
Volume:8 Issue: 2, Spring 2019

In this research, Ride quality of a three-axle truck is investigated to understand its vibration specifications and influence of it on special load. The truck is Benz 2624, and the load is rather sensitive to vibrations. The system is considered for an off-road duty. Hence, the vehicle is modeled as a nineteen-degree of freedom system and its equations of motion are derived by employing Lagrange equation. Since, the physical parameters of the vehicle were not available; the truck is modeled in Solidworks CAD software in order to obtain the material and dynamic properties of each component of the truck. Then, a code is developed in MATLAB to calculate natural frequencies and mode shapes of the truck and their corresponding vibrating components in critical speed. A simple model of the truck in ADAMS is employed for validation. The adoption of the results verifies the equations. The developed model can also be used in newer truck with some modifications. It is also necessary to have accurate data for input information in order to change thecurrent model for other utilities.

Nowadays, energy consumption management is a vital strategy for societies to optimize energy consumption. Considering the widespread functions of electrical energy in human lives,a high proportion of consumption management procedures deals with the management of electrical energy consumption. It is important to study the state of electrical energy and provide managerial and optimal management solutions in this industry. The main purpose of this study is ranking the key solutions of reducing electrical energy consumption in Isfahan Sepahan Cement industry. In this research, firstly, by studying and investigating conducted researches, interviewing with cement industry experts and alsoa researcher-made questionnaire, 20 solutions and 5 indices are chosen. Then by utilizing the indices weight and fuzzy TOPSIS method, solutions are ranked and in conclusion, after conducting needed calculations, “Hot exhaust gases heat recovery and electricity generation” obtained the highest rank and “Revision of various energy tariffs” scored the lowest rank.

Equal channel angular rolling (ECAR) process is one of the severe plastic deformation (SPD) methods that have been used to make ultra-fine grain (UFG) materials with improving the mechanical properties of samples. After performing the process at several paths, a large strain is applied to the material that can cause decreasing the grain size and improving the mechanical and physical properties of the metal. In this paper, the effects of annealing thermal treatment at various temperatures and times on the weld bond of bimetal explosive welded stainless steel-copper sheet during the equal channel angular rolling process have been investigated. For this purpose, after performing the ECAR process and thermal treatment on bimetal sheet, hardness and welding interface were studied. The results showed that performing thermal treatment at different temperatures caused the formation of intermetallic compounds in the weld bond, which would change the hardness of this region. Also, increasing the annealing time increased the thickness of the weld bond.

In this research, the effects of parameters include tool rotational and traverse speeds were investigated on heat generation and material flow during friction stir welding of Ti-6Al-4V alloy with computational fluid dynamics (CFD) method. Simulation results showed that with increasing of tool rotational and decreasing tool traverse speed, the more frictional heat generates which causes formation of bigger stir zone. Results indicate that the rotation of the shoulder can accelerate the material flow behavior near the top surface. The temperature field in the friction stir welding of Ti-6Al-4V alloy was anti symmetric to the welding line. Due to the results the heat generation and temperature distribution at advancing side were more than retreating side in all joint conditions. According to the results unsmooth and disarray flow patterns were formed in stir zone which caused formation of banded layer structure in advancing side. Due to results the torque decreases with an increase in the tool rotation speed due to increases in the heat generation rate and temperature, but torque is not significantly affected by the change in welding speed. The computed pressure field was higher in front of the tool compared to the trailing edge, and it is because pressure difference is required for flow occur. According to the selected parameters in this study, maximum temperature was produced in 800rpm tool speed and the computed strain rate and pressure of workpiece in this speed were 2.3 s-1, 0635 MPa, respectively.

Gas turbine disks usually operate at very high temperatures and rotate at very high angular velocities under normal working conditions. High temperature in turbine disks causes changes in their properties. High angular velocity creates a large centrifugal force in the disk and high temperature reduces the strength of the material and causes deformation. Complexity of these parameters has turned the determination of stress distribution in gas turbine disks to one of the bottlenecks in the analysis, design and manufacturing of turbine engines. Therefore, using an applicable method for stress analysis is essential in order to better determine stress distribution in turbine disks. In this study, the finite element method (FEA) is used for predicting the behavior of rotating disks under mechanical and thermal stresses. In order to increase the certainty of simulation, gas turbine disk is first simulated and analyzed based on dimensions and loading conditions extracted from previous studies. Then, the results are compared with previous studies in order to determine the accuracy of analysis method applied in ANAQUS software. Afterwards, gas turbine disks are evaluated under both rotational movement and temperature gradient. The results show that the presence of angular velocity and centrifugal force cause expansion to the disk radius. The results show an acceptable correlation between the results of empirical and numerical studies. According to the results, the approach proposed in this study is a suitable method for analysis of the stress, temperature and displacement in turbine disks and other components with similar functions.

Recent developments in the fields of electronic and digital telecommunications and creating low consumption compact circuits in nano dimensions have provided the ability to create sensors with low consumption power, small size, suitable cost, and various usages in the medical field. In past years, most of the researchers focused on sensor networks of the human body for designing wireless sensor, minimizing and matching them with live fibers of the body, lowering the consumption power, better signal processing, and communicational protocols and their security. Since the importance of sensor networks in the medical field, an entirely different method has been offered in this paper. It is based that we can manage nodes by changing the place of sensors, somehow that if the consumption powers of inside sensors are defined, then the power of all sensors will tend zero in a short period. Several various cost functions were offered based on the designed method, which created the most symmetrical kind of consumption and the lowest consumption in nodes. Then some optimality has been created in the selection of nodes in two modes of main and usual, by firefly ultra-complete algorithm. The offered method is better than the last methods because if the amounts nodes get increased, it will correctly keep its utility. After designing the costs function, the offered network has been implemented with software, and the results haves hown that in all fields, in terms of quality and consumption power form, the offered method has more utilization than other methods in the same terms.