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Advanced Design and Manufacturing Technology - Volume:14 Issue: 2, Jun 2021

International Journal of Advanced Design and Manufacturing Technology
Volume:14 Issue: 2, Jun 2021

  • تاریخ انتشار: 1400/05/13
  • تعداد عناوین: 11
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  • Alireza Arghavan, Ali Ghoddosian *, Ehsan Jamshidi Pages 1-14
    The Non-destructive vibration based structural damage detection techniques have been developed in the recent decades. They are usually converted into a mathematical optimization problem that should be solved using optimization algorithms. In this paper, a new hybrid algorithm, using a particle swarm - genetic optimization, is proposed that is called Swarm Life Cycle Algorithm (SLCA). Additionally, Modified Total Modal Assurance Criterion (MTMAC) that is modal based and involved natural frequencies and mode shapes, is used as an objective function. A cantilever beam is modelled and simulated using finite element method as a numerical case study with several different damage scenarios. To compare the effectiveness of the proposed algorithm with GA and PSO, they are applied to detect the locations and severities of damages of numerical cases separately. To assess the robustness of them, the effects of environmental noise, coordinate and mode incompleteness on the accuracy of damage detection have investigated. For experimental validation of the proposed method, empirical studies of single and double crack aluminium cantilever beams were conducted. The numerical and experimental results show that the proposed algorithm has great potential in crack identification. It is observed that SLCA is able to detect the location and extent of damage irrespective of the noise level and perform well in the presence of mode and coordinate incompleteness.
    Keywords: Damage Detection, Genetic Algorithm, Hybrid algorithm, Modal Properties, particle swarm optimization
  • Sajjad Dehghanpour, Mohsen Rahmani * Pages 15-22
    In this paper, crushing length, deformations and energy absorption of thin walled square and rectangular composite tubes which are reinforced with Aluminium and SMA wires and without wire have been investigated under a quasi-static lateral load, both experimentally and numerically. To experimental study, square and rectangular composite tubes have been fabricated with SMA wire, Aluminium wire and without wire. To validate the results, a finite element model is constructed and analysed under the same conditions by using FEM27 and LS-DYNA software packages for composite tubes with Aluminium wire and without wire. The numerical results are in a good agreement with the experimental data. The results show that section geometry and the types of reinforcement wires have a considerable effect on the energy absorption. Rectangular cross-section samples with SMA wires have the most energy absorption capacity.
    Keywords: Absorbed-Energy, Composite Tubes, Quasi- Static Load, SMA Wires
  • Ali Shahabi, Amir Hossein Kazemian *, Said Farahat, Faramarz Sarhaddi Pages 23-35
    In order to study on the vehicle’s dynamic behavior, this study presents a new dynamic modeling of the vehicle by considering the engine dynamics. The coordinate systems are considered separately for the sprung mass and unsprung masses. By using Newton’s equations of motion, the force-torque equations of the sprung mass and unsprung masses are derived in the vehicle coordinate system. In general, the sprung mass in modeling of the vehicle is considered as a rigid body. However, in this study the components rotation of the sprung mass such as the engine crankshaft is considered and its gyroscopic effects are exerted in the governing equations. The lateral and longitudinal forces of the tire are evaluated by Pacejka model. In fishhook maneuver, the vehicle's dynamic behavior is studied by the numerical simulation method under the supervision of the National Highway Traffic Safety Administration (NHTSA). The numerical simulation results are also validated by ADAMS/Car software. According to the results, the 15-DOF model in this research simulates the vehicle’s dynamic behavior with a good accuracy and the maximum roll rate of the vehicle reaches about 37 degrees per second.
    Keywords: Crankshaft, Gyroscopic Effects, Pacejka Model, Vehicle Coordinate System
  • Ali Saberi Varzaneh *, Mahmood Naderi Pages 37-48
    The proper connection between mortar and steel is one of the crucial issues in civil engineering. This paper has investigated the effect of polypropylene fibbers on the bond between cement mortar and steel, using “Twist-off” and “pull-off” tests. Moreover, in order to assess the in-situ mechanical properties of fibre-reinforced mortars, the correlation of records obtained from semi-destructive methods of “Twist-off” and “pull-off” with those of laboratory tests was determined, and calibration curves were provided, using the regression analyses. The mentioned tests were modelled with the ABAQUS software to evaluate the distribution of stresses and cracks developed during the semi-destructive tests. The results show that the addition of polypropylene fibbers reduces the shrinkage of mortars by about 13% and this has a direct effect on the bond between the mortar and steel. So that the shear and tensile bond of fibre-reinforced mortars at 90 days is 75% and 94% higher than conventional mortars, respectively. The reason for this is the effect of fibbers on the process of hydration of mortars and also to prevent excessive opening of cracks, which is shown by SEM. According to the results, instead of using an expensive and imported pull-off device, a cheap and internal twist-off device can be used to measure adhesion. Also, to evaluate the compressive strength of mortars, twist-off and pull-off tests can be used by placing the readings obtained in the equations y = 0.156x + 0.329 and y = 0.055x-0.001 instead of x, respectively, to evaluate the compressive strength of mortars.
    Keywords: Bond, Fibre, Finite Element Method, Mortar, Steel
  • Parham Rajabi, Hossein Rahmani *, Alireza Amiri Pages 49-63
    In this paper, the analysis and optimization of the effect of the materials distribution on the behavior of 2D functionally graded media subjected to impacted loading has been investigated. First, it is assumed that there are two cases for distributing the components in the FG material. In the first case, the power law is considered for materials distribution, and in the second case, the volume fractional changes of the components are made by third degree interpolation. Considering the elastodynamic behavior of the FG materials under loading, the general governing equations of the wave propagation are extracted for the case of properties variation in two dimensions and then the equations are solved using the finite difference method. Finally, an optimization has been made using a single objective genetic algorithm. The results show that the materials distribution has a considerable effect of stress wave propagation in FGMs.
    Keywords: Functionally graded material, finite difference method, Genetic Algorithm, Optimization, Stress Wave Propagation
  • Hossein Alian Moghadam, Majid Jabbari *, Saeed Daneshmand, Saeid Rasouli Jazi, Arezoo Khosravi Pages 65-71
    Needle graphite electrodes are one of the main parts used in electric arc furnaces. These electrodes have a significant impact on melt quality and product quality, and their consumption is one of the most important parameters of steel production cost in EAF furnaces. Therefore, reducing the consumption of needle graphite electrodes in these furnaces is very important. The main reasons for continuous use of needle graphite electrodes in arc furnaces are oxidation of the sidewalls and sublimation of their tips, and many solutions have been proposed to reduce them. In the present study, the effect of coating consisting of TiO2/SiC/SiO2 elements on the wear rate of the needle graphite electrode in the sublimation state is investigated using EDM (Electrical Discharge Machining- Spark device). For this purpose, the effect of voltage, current, pulse on time and pulse off time on the electrode wear rate are investigated and in this regard, Taguchi design method has been used to reduce the number of experiments. Based on the test results, TiO2/SiC/SiO2 coating reduces the wear rate of the needle graphite electrode due to sublimation.
    Keywords: Electric Arc Furnace, Electrode Consumption, Electrical discharge machining, Electrode Coating, Needle Graphite Electrode, Oxidation, Sublimation
  • Zahra Ghahramani, Masoud Zareh *, Hossein Pourfarzaneh, Farshad Pazooki Pages 73-83
    In this study, an annular combustion chamber of a turbojet engine with a net trust of 1650N is designed. Kerosene is considered as fuel in this study. The design consists of evaluation of the reference quantities, calculation of the required dimensions, estimation of air distribution and pressure drop, estimation of the number and diameter of air admission holes, as well as aerodynamic considerations. The design process is accompanied by Computational Fluid Dynamics (CFD) based on RANS simulation. Three-dimensional simulation of the reacting process within the combustion chamber is carried out based on the finite volume method. The RNG turbulent model and the finite rate/eddy dissipation combustion model are considered in the present study. Finally, the (atmospheric test) AT rig of the combustion chamber is explained. The Turbine Inlet Temperature (TIT) of combustion chamber is measured at different operating conditions. The TIT values in the numerical simulation and experimental measurement are 1191.1K and 1227 K, respectively, in the design point. The SN and the angle of the RZ are equal to 0.9955 and 35.26 degree, respectively. The temperature, velocity and pressure fields of RZ, air-fuel mixture, combustion turbulence are then presented in image outputs and graphs. The results indicate that the temperature distribution at the outlet of combustion chamber is relatively uniform.
    Keywords: Annular Combustion Chamber, Atmospheric Test (AT), 3D Numerical Simulation, Swirler Number (SN)
  • Behzad Bayati Chaleshtori, Ali Hajiahmad *, Seyed Saeid Mohtasebi Pages 85-92
    In this study, the characteristics of rectangular Kirchhoff nano-plate vibrations are investigated using a modified couple stress theory. To consider the effects of small-scale, the modified couple stress theory proposed by Young (2002) is used as it has only one length scale parameter. In modified couple stress theory, the strain energy density is a function of the components of the strain tensor, curvature tensor, stress tensor, and symmetric part of the couple stress tensor. After obtaining the strain energy, external work, and kinetic energy equation and inserting them in the Hamilton principle, the main and auxiliary equations of nano-plate are obtained. Then, by applying the boundary and force conditions in the governing equations, the vibrations of the rectangular Kirschhof nano-plate with the thickness are investigated with simple support around. The solution method used in this study is the Navier method and the effects of material length scale, length and thickness of the nanoplate on the vibration are investigated and the results are presented and discussed in details.
    Keywords: Kirchhoff Plate, Navier Solution Method, Modified couple stress theory, Rectangular Nano-Plate, vibrations
  • Alireza Pezhman, Javad Rezapour *, Mohammadjavad Mahmoodabadi Pages 93-110
    Accurate trajectory tracking and control of the Double Flexible Joint Manipulator lead to design a controller with complex features. In this paper, we study two significant strategies based on improving the structure of the hybrid controller and training the controller parameters for an online estimation of time-varying parametric uncertainities. For this purpose, combination of feedback linearization with an adaptive sliding mode control by considering update mechanism is utilized to stabilize the DFJM system. The update mechanism is obtained based on gradient descend method and chain rule of the derivation. Following, in order to eliminate the tedious trial-and-error process of determining the control coefficients, an evolutionary algorithm (NSGA-II) is used to extract the optimal parameters by minimizing the tracking error and control input. In the second step, an online estimation of the designed parameters were proposed based on three intelligent methods; weighting function, Adaptive Neural Network Function Fitting (ANNF), and adaptive Neuro-fuzzy inference system (ANFIS-PSO). The proposed controller reliability finally was examined in condition of the mass and the length of the robot arm was changed and sudden disturbances were imposed at the moment of equilibrium position, simultanously. The results of the tracking error and control input of the trained proposed controller demonstrated minimal energy consumption and shorter stability time in condition that the control parameters are constant and training are not considered.
    Keywords: Double Flexible Joint Manipulator, Gradient Descent Method, sliding mode controller, Uncertainy
  • Reza Tarighi, Amir Hooshang Mazinan *, Mohammad Hosein Kazemi Pages 111-122
    This paper presents a new method for modeling and Attitude Control of Autonomous Helicopters (A.H.) based on a polytopic linear parameter varying approach using parameter set mapping with the Principal Component Analysis (PCA). The polytopic LPV model is extracted based on angular velocities and Euler angles, that is influenced by flopping angles, by generating a set of data over the different trim points. Because of the high volume of trim data, parameter set mapping based on (PCA) is used to reduce the parameter set dimension. State feedback control law is proposed to stabilize the system by introducing a Linear Matrix Inequality (LMI) set over the vertices models. The proposed controller is performed for an Autonomous Helicopter in different scenarios. All the scenarios are investigated with the PCA algorithm as a technique for reducing the computational volume and increasing the speed of solving the LMI set. The simulation results of implementing the planned controller on the nonlinear model of an autonomous helicopter in different scenarios show the effectiveness of the proposed scheme.
    Keywords: Attitude Control, Linear Matrix Inequality, Linear Parameter Varying, principal component analysis
  • Batuhan Izgi, Meltem Eryildiz *, Mirig&Uuml, L Altan Pages 123-130
    Additive Manufacturing (AM) has become popular for rapid prototyping and it is presently widely used in different branches of industry because of its advantages such as freedom of design, mass customization, waste minimization and the ability to manufacture complex shape. AM is the process of making 3D object from computer model data by depositing of material layer by layer. Topology optimization is iterative modifying the shape and optimizing material within a given designs space for load, boundary condition thus leading to weight reduction of components. Thus, to form lightweight components which have great advantage where energy consumption is minimal, topology optimization is used. Reducing weight and decreasing the material usage while keeping the product functions are the main challenges. Studies on the integration of the topology optimization and additive manufacturing, specifically mass reduction attract considerable attention. The topology optimization process is employed in this case study, to redesign a lightweight automotive brake pedal to show the potential of topology optimized design for additive manufacturing. As a result of this study 54.07% weight reduction was achieved in the total mass. The thermo- mechanical analysis for additive manufacturing showed that the part without topological optimization 108 MPa of stress and 1,099 mm of displacement were obtained and after optimization they were 196,1 MPa and 1,295 mm, respectively.
    Keywords: Additive Manufacturing, analysis, Light Weight, Topological Optimization