PREDICTION OF MOTION CHARACTERISTICS ON SWATH TYPE FLOATING STRUCTURE USING TWO-DIMENSIONAL FRANK CLOSE-FIT TECHNIQUE

Authors

  • Mas Murtedjo Department of Ocean Engineering Faculty of Marine Technology, Sepuluh Nopember Institute of Technology (ITS) ITS Campus - Sukolilo, Surabaya 60III - Indonesia
  • Eko B. Djatmiko Department of Ocean Engineering Faculty of Marine Technology, Sepuluh Nopember Institute of Technology (ITS) ITS Campus - Sukolilo, Surabaya 60III - Indonesia

Keywords:

SWATH, Frank Close Fit-technique, 2-D strip theory, sway, heave, roll, pitch, yaw, beam sea, quartering sea, head sea

Abstract

The unique shape of SWATH which consists of two submerged hulls connected to the cross deck via slender struts has brought an excellent sea keeping quality. This makes an extensive study on the SWATH motion characteristics an important part in its design process. This paper describes the utilization of mathematical model to predict such vessel motions based on the Frank Close-Fit technique combined with the well-known 2-D strip theory. This technique was applied to compute the radiation, incident wave excitation and diffraction compo nents. These three components are then substituted into 5-DOF differential equations for SWATH motion in regular wave to attain its motion responses, namely sway, heave, roll, pitch, and yaw. SWATH motions were identified due to beam sea ( (90Ëš) quartering sea (I35Ëš) and head sea (180Ëš). The results of computation generally are in good agreement with experimental data. Certain discrepancies, especially in the peak value of roll motion are primarily brought about the absence of viscous damping. Slight discrepancies in the horizontal mode of motions, namely surge and yaw, are identified due to the harnesses effec. applied to the physical model. It may be concluded at this stage that the mathematical model is considered appropriate to be applied in the preliminary design of SWATH type vessels .

References

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Published

2018-04-25

How to Cite

Murtedjo, M., & Djatmiko, E. B. (2018). PREDICTION OF MOTION CHARACTERISTICS ON SWATH TYPE FLOATING STRUCTURE USING TWO-DIMENSIONAL FRANK CLOSE-FIT TECHNIQUE. Jurnal Mekanikal, 18(2). Retrieved from https://jurnalmekanikal.utm.my/index.php/jurnalmekanikal/article/view/207

Issue

Section

Mechanical