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An on-line testing and analysis prototype, called TXWIN, for distribution power transformers is presented in this paper. TXWIN allows the user to perform no-load test, load-loss test, and ratio test automatically via Windows Graphic User Interfaces (GUI). It also contains other transformer performance tests: DC resistance measurement test, high tension test, and insulation test. The prototype also has the functions to analyze test results, generate customized reports, and store transformer data in database.

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Man, who has abundantly helpful and offered invaluable assistance, advice, and guidance throughout the work in every step of my research. His patient explanation and continuous encouragement have enlightened me to a more profound and extensive academic future. I am grateful to Asst/Prof. Jorg Uwe Schlüter for his support and concern throughout my thesis writing. I would like to take this opportunity to thank the staffs of CNC lab, Fluid Mechanics Lab technician Mr. Yap Pow Kim and Thermal Fluid Research lab 1 technician Mr. Yuen Kee Hock for the help and suggestions in the setup of my experiment test rig. In addition, I would like to thank all the students in the researcher room 2 for their help and suggestions. Besides I would like to take this opportunity to express my appreciation to Dr. Song Yan Xi and Mr. Chiew Wei Ming for their constant suggestions for my work. Last but not least, I would like to thank my family and especially to my wife. This thesis is impossible without their support and encouragement.

Unsteady viscous flows past blunt bodies are simulated at the Reynolds numbers of 100, 200, 300, and 400. This research focuses on understanding the effects of the Reynolds numbers and blunt body shapes on the unsteady lift and drag forces. The incompressible Navier-Stokes flow solver, which employs the SIMPLER method in the twodimensional body-intrinsic orthogonal curvilinear coordinate system, is verified by comparing the present numerical results with currently available experimental and numerical data. In conclusion, it is observed that the body shapes and the Reynolds numbers affect significantly the frequencies of the force oscillations as well as the mean values and the amplitudes of the drag and lift force oscillations.