Javad Jafari

[ 1 ] - Damage detection and structural health monitoring of ST-37 plate using smart materials and signal processing by artificial neural networks

Structural health monitoring (SHM) systems operate online and test different materials using ultrasonic guided waves and piezoelectric smart materials. These systems are permanently installed on the structures and display information on the monitor screen. The user informs the engineers of the existing damage after observing signal loss which appears after damage is caused. In this paper health...

[ 2 ] - Stress Concentration Factor in a Functionally Graded Material Plate around a Hole

Stress concentration factors have been examined in a functionally graded material (FGM) plate with central holes in different shapes in this essay. The material properties change along the thickness of plate. ABAQUS software has been utilized for modeling of problem in which subroutine of ABAQUS sub-program was used for modeling of the targeted material. The considering shapes for hole in plate...

[ 3 ] - Numerical and Analytical Investigation of a Cylinder Made of Functional Graded Materials under Thermo-Mechanical Fields

This research develops thermo-elastic analysis of a functionally graded cylinder under thermo-mechanical loadings. Heat conduction equation in cylindrical coordinate system is solved. Thermal conductivity coefficient is graded along the radial direction. By considering a symmetric distribution of temperature, loading and boundary conditions, strain-displacement and stress-strain relations can b...

[ 4 ] - بررسی تاثیر پارامترهای موثر بر الگوی قرارگیری بهینه عملگرهای پیزوالکتریک در کاهش تمرکز تنش با استفاده از الگوریتم پرندگان

در این مقاله به بررسی پارامترهای موثر بر الگوی بهینه قرارگیری عملگرهای پیزوالکتریک در اطراف یک سوراخ در یک صفحه تحت کشش به منظور کاهش تمرکز تنش پرداخته شده است. بدین منظور، یک نسبت سفتی که در آن پارامترهای موثر بر جایابی عملگرهای پیزوالکتریک در اطراف سوراخ نشان داده ارائه شده است. در این نسبت سفتی، چهار پارامتر مدول الاستیسیته، ضخامت ورق، ضخامت پیزوالکتریکها و ولتاژ اعمالی به عملگرهای پیزوالکت...

[ 5 ] - Elastic Behavior of Functionally Graded Two Tangled Circles Chamber

This paper presents the numerical elastic solution for a real problem, functionally graded chamber of hydraulic gear pumps under internal pressure. Because of the similarity and complexity for the considering geometry, a bipolar cylindrical coordinate system is used to extract the governing equations. The material properties are considered to vary along the two tangled circles with a power-law ...

[ 6 ] - Stress Concentration Factor in a Functionally Graded Material Plate around a Hole

Stress concentration factors have been examined in a functionally graded material (FGM) plate with central holes in different shapes in this essay. The material properties change along the thickness of plate. ABAQUS software has been utilized for modeling of problem in which subroutine of ABAQUS sub-program was used for modeling of the targeted material. The considering shapes for hole in plate...

[ 7 ] - Numerical and Analytical Investigation of a Cylinder Made of Functional Graded Materials under Thermo-Mechanical Fields

This research develops thermo-elastic analysis of a functionally graded cylinder under thermo-mechanical loadings. Heat conduction equation in cylindrical coordinate system is solved. Thermal conductivity coefficient is graded along the radial direction. By considering a symmetric distribution of temperature, loading and boundary conditions, strain-displacement and stress-strain relations can b...

[ 8 ] - 3D Optimization of Gear Train Layout Using Particle Swarm Optimization Algorithm

Optimization of the volume/weight in the gear train is of great importance for industries and researchers. In this paper, using the particle swarm optimization algorithm, a general gear train is optimized. The main idea is to optimize the volume/weight of the gearbox in 3 directions. To this end, the optimization process based on the PSO algorithm occurs along the height, length, and width of t...