Discussion on “Layer-type transformer-winding cooling factors derived from analogue solution of the governing equations”

The objective of this paper is to analyze an unsteady MHD free convective heat and mass transfer boundary flow past a semi-infinite vertical porous plate immersed in a porous medium with radiation and chemical reaction. The governing equations of the flow field are solved numerical a two term perturbation method. The effects of the various parameters on the velocity, temperature and concentration profiles are presented graphically and values of skin-frication coefficient, Nusselt number and Sherwood number for various values of physical parameters are presented through tables.

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Propagation and Reflection of Plane Waves in a Rotating Magneto-Elastic Fibre-Reinforced Semi Space with Surface Stress

Mechanics and Mechanical Engineering ◽

10.2478/mme-2018-0074 ◽

2020 ◽

Vol 22 (4) ◽

pp. 939-958

Author(s):

Indrajit Roy ◽

D. P. Acharya ◽

Sourav Acharya

Keyword(s):

Surface Stress ◽

Incident Angle ◽

Plane Waves ◽

Three Dimensional ◽

Elastic Fibre ◽

Amplitude Ratios ◽

Governing Equations ◽

Rotation Surface ◽

Wave Velocities ◽

Magnetic Field Rotation

AbstractThe present paper investigates the propagation of quasi longitudinal (qLD) and quasi transverse (qTD) waves in a magneto elastic fibre-reinforced rotating semi-infinite medium. Reflections of waves from the flat boundary with surface stress have been studied in details. The governing equations have been used to obtain the polynomial characteristic equation from which qLD and qTD wave velocities are found. It is observed that both the wave velocities depend upon the incident angle. After imposing the appropriate boundary conditions including surface stress the resultant amplitude ratios for the total displacements have been obtained. Numerically simulated results have been depicted graphically by displaying two and three dimensional graphs to highlight the influence of magnetic field, rotation, surface stress and fibre-reinforcing nature of the material medium on the propagation and reflection of plane waves.

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Research Situation Analysis of On-line Detection Technology for Power Transformer Winding Deformation

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096513666191224112029 ◽

2020 ◽

Vol 13 (6) ◽

pp. 823-832

Author(s):

Zhenhua Li ◽

Weihui Jiang ◽

Li Qiu ◽

Zhenxing Li ◽

Yanchun Xu

Keyword(s):

Detection Method ◽

Theoretical Research ◽

Line Detection ◽

Response Analysis ◽

Advantages And Disadvantages ◽

Detection Technology ◽

The Future ◽

Transformer Winding ◽

On Line ◽

Winding Deformation

Background: Winding deformation is one of the most common faults in power transformers, which seriously threatens the safe operation of transformers. In order to discover the hidden trouble of transformer in time, it is of great significance to actively carry out the research of transformer winding deformation detection technology. Methods: In this paper, several methods of winding deformation detection with on-line detection prospects are summarized. The principles and characteristics of each method are analyzed, and the advantages and disadvantages of each method as well as the future research directions are expounded. Finally, aiming at the existing problems, the development direction of detection method for winding deformation in the future is prospected. Results: The on-line frequency response analysis method is still immature, and the vibration detection method is still in the theoretical research stage. Conclusion: The ΔV − I1 locus method provides a new direction for on-line detection of transformer winding deformation faults, which has certain application prospects and practical engineering value.

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The Analysis on Temperature Raise of EHV Transformer Winding Based on the oil dissolved gas analysis Technology

Asia-Pacific Journal of Advanced Research in Electrical and Electronics Engineering ◽

10.21742/ajaeee.2017.1.1.07 ◽

2017 ◽

Vol 1 (1) ◽

pp. 54-60

Author(s):

Xue Peng ◽

◽

Wei Wei ◽

Wang Ying ◽

Lu Xiuhe ◽

...

Keyword(s):

Gas Analysis ◽

Dissolved Gas ◽

Dissolved Gas Analysis ◽

Transformer Winding

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A New Analytical Approach for Nonlinear Global Buckling of Spiral Corrugated FG-CNTRC Cylindrical Shells Subjected to Radial Loads

Applied Sciences ◽

10.3390/app10072600 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2600

Author(s):

Tho Hung Vu ◽

Hoai Nam Vu ◽

Thuy Dong Dang ◽

Ngoc Ly Le ◽

Thi Thanh Xuan Nguyen ◽

...

Keyword(s):

Analytical Approach ◽

Cylindrical Shells ◽

Equation System ◽

Functionally Graded ◽

Governing Equations ◽

Reinforced Composite ◽

Global Buckling ◽

Homogenization Model ◽

Corrugated Structure ◽

The Galerkin Method

The present paper deals with a new analytical approach of nonlinear global buckling of spiral corrugated functionally graded carbon nanotube reinforced composite (FG-CNTRC) cylindrical shells subjected to radial loads. The equilibrium equation system is formulated by using the Donnell shell theory with the von Karman’s nonlinearity and an improved homogenization model for spiral corrugated structure. The obtained governing equations can be used to research the nonlinear postbuckling of mentioned above structures. By using the Galerkin method and a three term solution of deflection, an approximated analytical solution for the nonlinear stability problem of cylindrical shells is performed. The linear critical buckling loads and postbuckling strength of shells under radial loads are numerically investigated. Effectiveness of spiral corrugation in enhancing the global stability of spiral corrugated FG-CNTRC cylindrical shells is investigated.

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