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Full-Text Articles in Mechanical Engineering
Oscillating Flow In Channels With Sudden Change In Cross Section, Mounir B. Ibrahim, Waqar Hashim
Oscillating Flow In Channels With Sudden Change In Cross Section, Mounir B. Ibrahim, Waqar Hashim
Mechanical Engineering Faculty Publications
In this paper, we have computationally examined oscillating flow (zero mean between) two parallel plates with a sudden change in cross section. The flow was assumed to be laminar incompressible with the inflow velocity uniform over the channel cross section but varying sinusoidally with time. The cases studied cover wide ranges of Remax (from 187.5 to 2000), Va (from 1 to 10.66), the expansion ratio (1:2 and 1:4) and Ar (2 and 4). Also, three different geometric cases were discussed: (a) asymmetric expansion/contraction; (b) symmetric expansion/contraction; and (c) symmetric blunt body. For these oscillating flow conditions, the fluid …
A Fringe Center Detection Technique Based On A Sub-Pixel Resolution, And Its Applications Using Sinusoidal Gratings, Ming Chang, Paul P. Lin, Wen Chih Tai
A Fringe Center Detection Technique Based On A Sub-Pixel Resolution, And Its Applications Using Sinusoidal Gratings, Ming Chang, Paul P. Lin, Wen Chih Tai
Mechanical Engineering Faculty Publications
A common problem in optical profilometry is the accuracy in locating fringe centers. This paper presents an accurate fringe center detection technique based on sub-pixel resolution using the fringe projection method. An optimum reconstruction filter is developed which has low sensitivity to noise. In fringe center detection, computer simulation results of using one-pixel and sub-pixel resolutions are compared. The detection technique is then applied to radius measurement of cylindrical objects and surface profile measurement of diffuse objects. The experimental results thus obtained through the proposed optimum reconstruction filter show significant improvement in measurement accuracy.