• Title/Summary/Keyword: Riblet

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3D Elastic Contact Analysis of Sharkskin Surface Pattern (상어 표피 형상의 3차원 탄성접촉해석)

  • Kim, Tae Wan
    • Tribology and Lubricants
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    • v.28 no.6
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    • pp.297-302
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    • 2012
  • We conducted 3D elastic contact analysis of a sharkskin surface pattern for the characteristic assessment of biomimetic shark skin structure pattern for engineering applications. Rough sharkskin surfaces of similar size with real shark skin scales are generated numerically. Under the assumption of the contact of a plate on the generated sharkskin surface, contact performances such as contact pressure, real contact area, and surface separation are evaluated.

Evaluation of Recursive PIV Algorithm with Correlation Based Correction Method Using Various Flow Images

  • Daichin;Lee, Sang-Joon
    • Journal of Mechanical Science and Technology
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    • v.17 no.3
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    • pp.409-421
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    • 2003
  • The hierarchical recursive local-correlation PIV algorithm with CBC (correlation based correction) method was employed to increase the spatial resolution of PIV results and to reduce error vectors. The performance of this new PIV algorithm was tested using synthetic images, PIV standard images of Visualization Society of Japan, real flows including ventilation flow inside a vehicle passenger compartment and wake behind a circular cylinder with riblet surface. As a result, most spurious vectors were suppressed by employing the CBC method, the hierarchical recursive correlation algorithm improved the sub-pixel accuracy of PIV results by decreasing the interrogation window size and Increased spatial resolution significantly. However, with recursively decreasing of interrogation window size, the SNR (signal-to-noise ratio) in the correlation plane was decreased and number of spurious vectors was increased. Therefore, compromised determination of optimal interrogation window size is required for given flow images, the performance of recursive algorithm is also discussed from a viewpoint of recovery ratio and error ratio in the paper.