Gürkan Şakar - Academia.edu (original) (raw)

Papers by Gürkan Şakar

World Academy of Science, Engineering and Technology, International Journal of Mechanical and Mechatronics Engineering, Jul 1, 2015

International Journal of Mechanical Sciences, 2003

... method. Kar [22] determined the stability of a rotating pretwisted non-uniform viscoelastic c... more ... method. Kar [22] determined the stability of a rotating pretwisted non-uniform viscoelastic cantilever beam subjected to a tangential force applied at its free end by a method of approximation based on an adjoint variational principle. ...

International Journal of Mechanical Sciences, Sep 1, 2003

World Academy of Science, Engineering and Technology, International Journal of Aerospace and Mechanical Engineering, 2016

Materials Characterization, 2001

The ion nitriding behavior of AISI 8620 alloy steel has been examined under varying process condi... more The ion nitriding behavior of AISI 8620 alloy steel has been examined under varying process conditions. The process variables included time (1 ± 8 h), temperature (450 ± 600°C) and a 70% H 2 ± 30% N 2 gas mixture. The structure of the compound layer was studied by X-ray diffraction (XRD) and light optical microscopy. These studies showed that the thickness of the compound layer increased with increasing time at 500°C and 550°C; however, at 600°C, the thickness of the compound layer decreased with increasing time. Phase changes during ion nitriding at 600°C have been investigated using XRD, scanning electron microscope (SEM) and energy dispersive spectrometry (EDS). The maximum surface hardness was obtained at 500°C for 8 h and a larger diffusion layer was obtained at 600°C for 8 h. A braunite layer formed at 600°C.

Journal of Constructional Steel Research

In this study, in-plane dynamic stability analysis of multi-span frames, which are composed of co... more In this study, in-plane dynamic stability analysis of multi-span frames, which are composed of columns and beams and subjected to periodic loading, is investigated by using the Finite Element Method. Periodic loading is considered to be applied to each column member as an axial load and no loading is applied on the beams. The effects of beam to column length ratio, beam to column cross-section ratio and beam to column moment of area ratio are investigated for in-plane frames. In addition, the effect of the number of span and static and dynamic load parameters on the free vibration, buckling and dynamic stability analysis is also investigated. The results are compared with the recent literature in terms of the fundamental natural frequency and critical buckling load.

This paper presents a finite element model for the static and dynamic stability study of a pretwi... more This paper presents a finite element model for the static and dynamic stability study of a pretwisted aerofoil cross-section rotating blade subjected to an axial periodic force. The blade is modeled as an Euler–Bernoulli beam and Bolotin&amp;amp;#39;s method is used to show the effects of coupling due to the shear center distance from the centroid, pretwist angles, rotational speeds and

International Journal of Mechanical Sciences, 2008

This paper presents a finite element model for the static and dynamic stability of a rotating pre... more This paper presents a finite element model for the static and dynamic stability of a rotating pretwisted aerofoil cross-section two-bladed packet subjected to uniform radial periodic force. The effects of various parameters such as shroud dimensions, pretwist angle, stagger angle, rotational speed and distance of shear center from the centroid on the stability of the blade packets are presented. The

International Journal of Mechanical Sciences, 2006

In this paper static and dynamic stability of rotating asymmetric cross-section two-bladed packet... more In this paper static and dynamic stability of rotating asymmetric cross-section two-bladed packets subjected to uniform radial periodic force are studied using the finite element method. The effects of various parameters such as shroud dimensions, stagger angle, rotational speed and distance of shear center from the centroid on the stability of the blade packets are presented. The numerical results indicate