• Steel and Composite Structures
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• v.38 no.2
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• pp.189-211
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• 2021

An analytical solution is presented to analyze the thermoelastoplastic response of a rotating thick-walled cylindrical pressure vessel made of functionally graded material (FGM). The analysis is based on Tresca's yield condition, its associated flow rule and linear strain hardening material behaviour. The uncoupled theory of thermoelasticity is used, and the plane strain condition is assumed. The material properties except for Poisson's ratio, are assumed to vary nonlinearly in the radial direction. Elastic, partially plastic, fully plastic, and residual stress states are investigated. The heat conduction equation for the one-dimensional problem in cylindrical coordinates is used to obtain temperature distribution in the vessel. It is assumed that the inner surface is exposed to an airstream and that the outer surface is exposed to a uniform heat flux. Tresca's yield criterion and its associated flow rule are used to formulate six different plastic regions for a linearly hardening condition. All these stages are studied in detail. It is shown that the thermoelastoplastic stress response of a rotating FGM pressure vessel is affected significantly by the nonhomogeneity of the material and temperature gradient. The results are validated with those of other researchers for appropriate values of the system parameters and excellent agreement is observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.4
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• pp.439-446
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• 2010

Fracture mechanics is used for the detailed analysis of the failure of high-speed rotating cylindrical vessels. The general procedure for the analysis of fatigue life and failure used in this study is summarized; the initial material properties are also described. The results of the theoretical stress analysis are compared to the observed magnitude of the stress under the operational condition. The fracture-surface configurations observed under both optical and scanning electron microscopes are used to investigate the progress of fatigue crack propagation. Fatigue life estimates obtained by using the Paris model are compared to the actual service life of the high-speed rotating pressure vessel.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.21-25
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• 2011

In order to monitor a rotating cylindrical separator for radioactive waste, an electrical resistance method is proposed and its mathematical model is investigated. In a rotating radioactive waste separator, the electrical resistance between a pair of electrodes mounted on the inner wall of the vessel is related to the thickness of annular region of insoluble particle formed around the periphery and the concentration of the insoluble particle in that region. This work presents an analytical relationship among the aforementioned parameters based on a two-dimensional solution to the electrical potential equation and an empirical conductivity-concentration relation. Also, the feasibility of electrical resistance method for monitoring rotating cylindrical separators is discussed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.3
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• pp.62-68
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• 2010

In the engineering field, sloshing in rolling vessel is a hot issue because of the connection with ship stability problem. The sloshing phenomena also can be utilized in the field of structure or facility vibration damper. This paper explores the possibility which sloshing of multi-particles can be used to dissipate energy in a rolling container. This energy dissipation can be utilized to the application of rotating damper. Some of the parameters expected to dissipates energy, such as vessel size, particle size, mass fraction and ramp height, have been experimentally and theoretically studied.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.363-370
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• 2017

This paper is concerned with the evaluation of mixing performance of a particle mixer, which consists of a vertical cylindrical vessel and a rotating impeller with several blades. We consider four design variables for the mixer blades, such as the angle, length, and number of blades, and the gap between the blades and the vessel bottom. The particle mixing process due to the impeller rotation is simulated using the discrete element method, and the mixing performance is quantitatively evaluated by introducing a mixing index. Analyzing the main effects and interactions of the four design variables through the design-of-experiments approach, it is concluded that the blade angle has the most dominant influence on the mixing performance whereas the gap has no significant influence. In addition, we determine the best combination of design parameters to maximize the mixing performance.