Design of ANFIS Control System Using Genetic Algorithm Optimization Method to Vibration Vibration on a Beam
R.
Azadian
کارشناس ارشد، دانشگاه گیلان
author
A.
Bagheri
Guilan
author
text
article
2017
per
One of the most important considerations in structures design are analysis and control of structure vibrations. Hence how to control and suppress vibrations is one of the important issue in the design of structures. Also, The dependence between mechanical and electrical properties of piezoelectric materials has led to the use of these materials as sensors and actuator to control the structural response is very good. In the present work the adaptive neuro fuzzy inference system with genetic optimization method is used. The method can be regarded as one of the modern methods for the analysis and design of complex systems and can be inaccurate. A finite element model based on Euler-Bernoulli beam and the linear theory of piezoelectric materials has been developed. The contribution of the piezoelectric sensor and actuator layers on the mass and stiffness of the beam has been considered with modeling of entire structure. The numerical results obtained from the active vibration control of the beam is provided with MATLAB. The results show that Using the case method can be settling time and Maximum over shoot displacement response of the beam can be reduced significantly.
Journal of Solid and Fluid Mechanics
Shahrood University of Technology
2251-9475
7
v.
4
no.
2017
1
11
http://jsfm.shahroodut.ac.ir/article_1164_ec773a624b961e2a149b3f65b523c685.pdf
dx.doi.org/10.22044/jsfm.2017.1820.1598
Experimental investigation and numerical simulation of solid fuel rocket engine internal ballistic
F.
Tavakolifar
کارشناسی ارشد، دانشکده مهندسی مکانیک، دانشگاه صنعتی اصفهان
author
M.M
Fakhari
دانشجوی دکترا، دانشکده مهندسی، دانشگاه بیرجند
author
text
article
2017
per
The present survey focuses on experimental and numerical investigation of internal ballistic of Solid Fuel Rocket Engine (SFRE) for three different grains: bottom back-burning, annular side back-burning and all-side back-burning. To validate the developed numerical solution some experiments were performed and numerical results were compared to them. Accordingly the numerical results were compatible with that of experimental in an acceptable fashion which means the applied numerical method was appropriate to predict the behavior of SFRE. According to result, ignoring the transient effects, the combustion chamber pressure increased with increasing the area of burning region and vice versa. Also with increasing the combustion chamber pressure the effects of erosion burning declined. The more the combustion chamber pressure, the more the engine performance and the more the specific impulse were. Mostly the bottom back-burning grains provided constant-area burning region and consequently a constant pressure profile. Also area of burning region followed increasing and decreasing patterns for annular side back-burning and all-side back-burning respectively.
Journal of Solid and Fluid Mechanics
Shahrood University of Technology
2251-9475
7
v.
4
no.
2017
13
24
http://jsfm.shahroodut.ac.ir/article_1165_cf01558751ea85fd2edf1fffaf90a074.pdf
dx.doi.org/10.22044/jsfm.2017.4496.2166
Free vibration and static deflection of a micro-plate with piezoelectric layers using modified couple stress theory
A.
Kazemi
دانشجوی کارشناسی ارشد، مهندسی مکانیک، دانشگاه شیراز، شیراز
author
R.
Vatankhah
استادیار، مهندسی مکانیک، دانشگاه شیراز، شیراز
author
M.
Farid
استاد، مهندسی مکانیک، دانشگاه شیراز، شیراز
author
text
article
2017
per
In this syudy, a size-dependent modeling of micro plate with piezoelectric layers based on classical plate theory using modified couple stress theory is developed in this paper. Introducing only one material length scale parameter in modified couple stress theory to take into account the size effect of the system is one of the main advantage of this theory over other nonclassical continuum mechanics theories. Also, this theory is able to predict and interpret the size-dependent static and dynamic behavior of micro-scale structures with more accuracy and precision in comparison to classical continuum mechanics theory. The piezoelectric layers are modeled according to linear piezoelectricity theory and due to small thickness, the electric field is assumed to be constant over the layers. The equation of motion and its corresponding boundary conditions are derived using Hamilton principle. The equation of motion is solved numerically using finite element method and the effect of material length scale parameter and piezoelectric layers on free vibration and static deflection of micro-plate are investigated.
Journal of Solid and Fluid Mechanics
Shahrood University of Technology
2251-9475
7
v.
4
no.
2017
25
34
http://jsfm.shahroodut.ac.ir/article_1166_f2dacc49c35f970e5bdef8ec12b86abe.pdf
dx.doi.org/10.22044/jsfm.2017.4785.2210
An Investigation for Nonlinear Dynamic Behavior of Flange Joints Under Lateral Loading
F.
Meisami
Ferdowsi university of mashhad
author
M.
Moavenian
Ferdowsi university of Mashhad
author
A.
Afshadfard
Ferdowsi university of mashhad
author
text
article
2017
per
Flange joints are one of the most widely used industrial and aerospace connection parts. Therefore, investigating the static and dynamic behavior of these joints is very important. In this study, a model consisting of two beams connected by a single screw flange joint is intended. Then a mass-spring model consisting of linear axial and nonlinear torsional springs is considered. Dynamic equations of the system are derived considering the beam equations, boundary conditions and compatibility equations. Assuming equivalent linear springs, bending frequencies and mode shapes for several joint stiffnesses are obtained. Using the mode superposition method and approximating the first mode, the dynamic equation is converted to a 1-DOF nonlinear stiffness equation. Curve approximation method is used to describe the nonlinear stiffness with equivalent polynomial equation. Then the perturbation method is used to solve the nonlinear equation of free and forced vibrations of the system, near natural frequencies, subharmonic and super harmonic regions. The numerical solution result of the bilinear and its equivalent polynomial equation is compared with the the perturbation method results. Accuracy of the results obtained by the polynomial approximation and perturbation solution is guaranteed by conformity of numerical and semi-analytical results. Then the effect of changing system parameters on the frequency response is studied. Finally, frequency response, which is obtained by the numerical and multiple scale perturbation methods is compared.
Journal of Solid and Fluid Mechanics
Shahrood University of Technology
2251-9475
7
v.
4
no.
2017
35
48
http://jsfm.shahroodut.ac.ir/article_1167_c87cb947e09f1f9f9c4f5df0871e955a.pdf
dx.doi.org/10.22044/jsfm.2018.5409.2322
Multi-objective optimization of electrochemical machining parameters using response surface methodology
A.
Mehrvar
Mechanical Engineering group, Faculty of Engineering, University of Shahreza
author
A.
Basti
دانشگاه گیلان، دانشکده فنی و مهندسی
author
A.
Jamali
Faculty of University of Guilan
author
text
article
2017
per
Electrochemical machining (ECM) process involves several physical and chemical phenomena that make it difficult to model the process.Therefore, selection of proper and optimal parameters setting is a challenging issue. In this paper, an approach is applied to look for the optimum solution to this problem. In this way, four parameters, i.e. voltage, tool feed rate, electrolyte flow rate and electrolyte concentration; and two machining criteria, i.e. material removal rate (MRR) and surface roughness (Ra) are considered as input variables and responses, respectively. Therefore, mathematical models have first been developed using response surface methodology (RSM). Then, the Derringer method has been utilized for optimizing the two responses simultaneously. MRR and Ra response would not be optimized in the same manner and have contradictive behaviors. The result of multi-objective optimization provides an optimal ECM process parameter setting, so the user can select desired optimal process parameters combination to achieve the optimal result. The optimal input parameters were determined as 25.56 V, 0.5 mm/min, 6.45 l/min, 138.1 g/l. Finally, optimization result was verified experimentally and the percentage error were 6.4 and 6.7 for MRR and Ra responses respectively.
Journal of Solid and Fluid Mechanics
Shahrood University of Technology
2251-9475
7
v.
4
no.
2017
49
60
http://jsfm.shahroodut.ac.ir/article_1168_01fe3e49087332f0575503c920f488ff.pdf
dx.doi.org/10.22044/jsfm.2017.4934.2233