Xiaowen Wu
Wuhan University

Published : 4 Documents
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Numerical Calculation of Transient Thermal Characteristics in Gas-Insulated Transmission Lines Li, Hongtao; Shu, Naiqiu; Li, Ling; Wu, Xiaowen
TELKOMNIKA Telecommunication, Computing, Electronics and Control Vol 11, No 3: September 2013
Publisher : Universitas Ahmad Dahlan

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Abstract

For further knowledge of the thermal characteristics in gas-insulated transmission lines (GILs) installed above ground, a finite-element model coupling fluid field and thermal field is established, in which the corresponding assumptions and boundary conditions are given.  Transient temperature rise processes of the GIL under the conditions of variable ambient temperature, wind velocity and solar radiation are respectively investigated. Equivalent surface convective heat transfer coefficient and heat flux boundary conditions are updated in the analysis process. Unlike the traditional finite element methods (FEM), the variability of the thermal properties with temperature is considered. The calculation results are validated by the tests results reported in the literature. The conclusion provides method and theory basis for the knowledge of transient temperature rise characteristics of GILs in open environment.
Ventilation Structure Improvement of Induction Motor Using Multiphysics Simulations Zhang, Yujiao; Huang, Xiongfeng; Huang, Tao; Ruan, Jiangjun; Wu, Xiaowen
TELKOMNIKA Telecommunication, Computing, Electronics and Control Vol 10, No 3: September 2012
Publisher : Universitas Ahmad Dahlan

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Abstract

Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joules losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM) is investigated to demonstrate the temperature distribution. The Joules losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way.
THERMAL ANALYSIS IN GAS INSULATED TRANSMISSION LINES USING AN IMPROVED FINITE-ELEMENT MODEL WU, Xiaowen; SHU, Naiqiu; LI, Hongtao; LI, Ling
Indonesian Journal of Electrical Engineering and Computer Science Vol 11, No 1: January 2013
Publisher : Institute of Advanced Engineering and Science

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Abstract

In this paper, an improved finite element (FE) model is proposed to investigate the temperature distribution in gas insulated transmission lines (GILs). The solution of joule losses in eddy current field analysis is indirectly coupled into fluid and thermal fields. As is different from the traditional methods, the surrounding air of the GIL is involved in the model to avoid constant convective heat transfer coefficient, thus multiple species transport technique is employed to deal with the problem of two fluid types in a single model. In addition, the temperature dependent electrical and thermal properties of the materials are considered. The steady-state and transient thermal analysis of the GIL are performed separately with the improved model. The corresponding temperature distributions are compared with experimental results reported in the literature. DOI: http://dx.doi.org/10.11591/telkomnika.v11i1.1247
VENTILATION STRUCTURE IMPROVEMENT OF INDUCTION MOTOR USING MULTIPHYSICS SIMULATIONS Zhang, Yujiao; Huang, Xiongfeng; Huang, Tao; Ruan, Jiangjun; Wu, Xiaowen
Indonesian Journal of Electrical Engineering and Computer Science Vol 10, No 3: July 2012
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Temperature rise analysis has significant impact in the design of air-cooled asynchronous induction motor. However, the affection cannot be accurately evaluated by using traditional empirical curves method due to the complexity of the inductor architecture. Considering Joule?s losses in stator windings and the induced eddy current in squirrel cages, and heat dissipation by air convection and solid conduction, in this paper a 3-D coupled-field finite-element method (FEM) is investigated to demonstrate the temperature distribution. The Joule?s losses calculated by 3-D eddy- current field analysis are used as the input for the thermal field analysis, which is deeply dependent on accurate air fluid field analysis. A novel multi-component fluid model is employed to deal with the influence of rotor rotation upon the air convection. The simulation results show the fatal influence of the ventilation structure and the effectiveness of the proposed cooling improvement way. DOI: http://dx.doi.org/10.11591/telkomnika.v10i3.605