EFFECT OF SURFACE ROUGHNESS ON DRAG OF LOGGERHEAD CARAPACE

Authors

  • Alan Chan Kah Poh Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 75450 Ayer Keroh, Melaka
  • Cheng See Yuan Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 75450 Ayer Keroh, Melaka
  • Ahmad Kamal Mat Yamin Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 75450 Ayer Keroh, Melaka
  • Ainil Jesita Jalaluddin Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, 75450 Ayer Keroh, Melaka
  • Iskandar Shah Ishak Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor
  • Shuhaimi Mansor Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor

Keywords:

Drag, roughness, carapace, wind tunnel

Abstract

The present investigation primarily studies the effect of surface roughness on the drag coefficient, Cd of a Loggerhead sea turtle carapace using a subsonic wind tunnel. The pressure coefficient, Cp distribution across the Loggerhead carapace was also investigated and is compared to the Cp trend of an airfoil in order to deduce the aerodynamics features of the Loggerhead carapace. One-to-five-scaled models are created based on the dimensions of a real Loggerhead turtle with simplification. Four roughness scales were employed to capture the Cd trend at increasing Reynolds numbers, Re. As expected, the Cd levelled off with Re for all four models investigated. However, the Re where constant Cd began varies with relative roughness of the carapace models. Good correlation between the Cd and relative roughness is obtained. In addition, the wind tunnel results are able to capture the Cp trend of the carapace models and compared to Cp values of an airfoil. Results reveal that the upper surface of the Loggerhead carapace is streamlined but with restrictions of angle of attack.

References

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Published

2018-04-09

How to Cite

Kah Poh, A. C., See Yuan, C., Mat Yamin, A. K., Jalaluddin, A. J., Ishak, I. S., & Mansor, S. (2018). EFFECT OF SURFACE ROUGHNESS ON DRAG OF LOGGERHEAD CARAPACE. Jurnal Mekanikal, 26(2). Retrieved from https://jurnalmekanikal.utm.my/index.php/jurnalmekanikal/article/view/137

Issue

Issue 26: December 2008 (Special Issue)

Section

Mechanical

License

Copyright of articles that appear in Jurnal Mekanikal belongs exclusively to Penerbit Universiti Teknologi Malaysia (Penerbit UTM Press). This copyright covers the rights to reproduce the article, including reprints, electronic reproductions or any other reproductions of similar nature.