Flutter phenomenon of a pressurized functionally graded cylindrical shell in aerodynamic supersonic flow based on the Flugge's theory
Mansoor
Darvize
نویسنده مسئول، استاد، گروه مهندسی مکانیک، دانشکده فنی، دانشگاه گیلان
author
Reza
Ansari
استادیار، گروه مهندسی مکانیک، دانشکده فنی، دانشگاه گیلان
author
Alireza
Shahrokhzadeh
دانشجوی کارشناسی ارشد، گروه مهندسی مکانیک، دانشکده فنی، دانشگاه گیلان
author
Raheb
Gholami
دانشجوی دکترا، گروه مهندسی مکانیک، دانشکده فنی، دانشگاه گیلان
author
text
article
2014
per
Prediction of the flutter phenomenon of a functionally graded cylindrical shell with simply supported end conditions under aerodynamic and thermal loadings with considering the internal pressure of the shell is investigated. The volume fraction of constituent materials follows a simple power law in the thickness direction. The aerodynamic load is defined by linearized first-order potential (piston) theory incorporating a correction term. The strain-displacement relations and the equations of motion are written in accordance with Flugge's shell theory in which initial stresses are taken from solution of equilibrium equations. The Galerkin method is used for solving the equations of motion. The effects of volume fraction distributions, temperaure and pressure variations on the flutter boundary and time response of the system are fully discussed.
Iranian Journal of Mechanical Engineering Transactions of ISME
ISME
2538-4775
16
v.
3
no.
2014
6
33
https://jmep.isme.ir/article_27218_e9ed1d34b87c2e5d3635ef71f8029068.pdf
Experimental and FEM analysis of incremental sheet forming, investigation of shape and plate thickness distribution
Mohsen
Nakhaei
ارشناسی ارشد، دانشگاه آزاد اسلامی، واحد نجف آباد، باشگاه پژوهشگران جوان و نخبگان، نجف آباد، ایران
author
Mahmood
Farzin
نویسنده مسئول، استاد، گروه مهندسی مکانیک، دانشگاه صنعتی اصفهان
author
Saeed
Amini
کارشناسی ارشد، انستیتو مهندسی مکانیک، دانشگاه فنی و حرفهای(مرکز مهاجر)، اصفهان
author
Mohsen
Loh Moosavi
استادیار، گروه مهندسی مکانیک، دانشگاه آزاد اسلامی، واحد خمینی شهر
author
text
article
2014
per
Incremental sheet forming is a novel process. In recent years considerable attention has been paid to perform this process more flexibly and controllably. For producing of parts by traditional forming processes tool and die are required and Construction of this equipment is a costly and time-consuming process, so does not need any die is one of advantages of this process. In incremental sheet forming there are many parameters that have significant impacts on the quality of final product. In this study, the FEM analysis of incremental sheet forming to achieve cone frustum by using clamp and rig was done. In this analysis, due to the complex tool path a Vdisp code was used. Experimental tests have been done in accordance with the analysis. By investigating the final shape and the thickness distribution along the sheet, it was shown that the code had modeled the tool path with a good accuracy and there was a good agreement between the FEM and experimental test results.
Iranian Journal of Mechanical Engineering Transactions of ISME
ISME
2538-4775
16
v.
3
no.
2014
34
46
https://jmep.isme.ir/article_27220_3317dad6131460a69950692c1afa77ba.pdf
Antiplane stress analysis of transversely isotropic circular plates weakened by multiple defects
Alireza
Hasani
دانشجوی دکترا، دانشکده مهندسی مکانیک، دانشگاه زنجان
author
Reza
Teymoori Faal
دانشگاه زنجان
author
text
article
2014
per
In this article, the antiplane stress analysis of a transversely isotropic circular plane weakened by multiple defects is accomplished. The solution of a screw dislocation problem in a circular plane is first obtained by means of a finite Fourier sin transform. Next, using the resultant dislocation solution, integral equations of the circular plane with arbitrary number of cracks are obtained. The numerical solution of ensuing integral equations which are of the Cauchy type singular leads to evaluation of dislocation density on the crack surfaces. Using corresponding dislocation density, the stress intensity factors of crack tips for some examples are attained.
Iranian Journal of Mechanical Engineering Transactions of ISME
ISME
2538-4775
16
v.
3
no.
2014
47
67
https://jmep.isme.ir/article_27223_0f94e40db893e66d3810cfaa242e8105.pdf
Comparison of shear fracture surfaces of drop weight and charpy test samples in thermomechanical steel
Hamid
Khanin
کارشناسی ارشد، دانشکده مهندسی مکانیک، دانشگاه بیرجند
author
Seyed Hojat
Hashemi
استاد، گروه پژوهشی مطالعات لوله و صنایع وابسته، دانشگاه بیرجند
author
text
article
2014
per
Any crack existence in the high-pressure gas transmission pipelines is potentially dangerous and can cause pipe explosion. Thus, the safety and structural resistance against crack growth is very important in pipeline design. In the present study, the Charpy impact test and drop weight tear test on standard test samples are conducted to evaluate the dynamic behavior of API X70 pipeline steel. The results showed that the shear fracture area (as the most important characteristic of steel strength under dynamic loading) was approximately 95% in drop weight tear test. The Charpy test specimen with average energy of 256 joules had 100% shear fracture surface. Fractography of the fracture surfaces of the test samples showed that dimple ductile fracture was the dominant fracture mode in the tested material.
Iranian Journal of Mechanical Engineering Transactions of ISME
ISME
2538-4775
16
v.
3
no.
2014
67
78
https://jmep.isme.ir/article_27228_0aa4744f64bc273a9c9a029f8c4c144b.pdf
Investigation of shape memory and super elasticity behaviors using various micromechanical models due to thermomechanical monotonic and cyclic loads
Mohammad
Shariyat
دانشیار، دانشکده مهندسی مکانیک، دانشگاه صنعتی خواجه نصیرالدین طوسی، قطب علمی سازههای هوشمند و سامانه های دینامیکی، تهران
author
Aydin
Ghaznavi
دانشجوی دکترا، دانشکده مهندسی مکانیک، دانشگاه صنعتی خواجه نصیرالدین طوسی، تهران
author
text
article
2014
per
In the present paper, accuracies of various micromechanical models in reproducing the one-dimensional shape memory and super elasticity behaviors are investigated. In this regard, Brinson’s model is extended based on the loading path dependency of the martensite volume fraction. Different loading paths including individual, combined, and cyclic variations of the temperature and stress are considered. It is generally assumed that the compressive material properties are different from the tensile ones. Furthermore, accuracy of results of the various loadings is evaluated based on the Young moduli predicted using the well-known Reuss, Voigt, and Mori-Tanaka (with spherical and elliptical shape factors) micromechanical homogenization techniques. Moreover, results of the prepared computer code are validated through comparing them with the experimental results available in the literatures. Results reveal that differences among predictions of the four micromechanical models are significant for the cyclic loadings.
Iranian Journal of Mechanical Engineering Transactions of ISME
ISME
2538-4775
16
v.
3
no.
2014
79
104
https://jmep.isme.ir/article_27232_285e11225edb36a546739f968a3b582a.pdf