THEORETICAL DETERMINATION OF PORPOISING INSTABILITY OF HIGH-SPEED PLANNING BOATS

A theoretical method is derived for predicting trim angle and speed coefficient at the inception of porpoising of prismatic planing hulls. Although equations are derived for the surge, pitch, and heave dgreees of freedon, it is seen that the effect of surge is small at ordinary operating trim angles. Comparisons of theoretical predictions with existing experimental data on coupled pitch and heave porpoising show reasonably good agreement for a wide range of speed coefficients, load coefficients, and deadrise angles. The theory may also be used for estimating the natural frequencies and damping characteristics of prismatic hulls in the stable high-speed planing range.

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  • Corporate Authors:

    Society of Naval Architects and Marine Engineers

    601 Pavonia Avenue
    Jersey City, NJ  United States  07306-2907
  • Authors:
    • MARTIN, M
  • Publication Date: 1978-3

Media Info

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Filing Info

  • Accession Number: 00173746
  • Record Type: Publication
  • Source Agency: Journal of Ship Research
  • Files: TRIS
  • Created Date: May 3 1978 12:00AM