Thyssen-Waas Ice Transit Bow Seakeeping Study

• Main Authors: Thomas III, William L., Lee, Wah T.
• Other Authors: DAVID TAYLOR RESEARCH CENTER BETHESDA MD SHIP HYDROMECHANICS DEPT
• Format: Text
• Language: English
• Published: 1991
• Subjects: Snow; Ice and Permafrost; Operations Research; Marine Engineering; Structural Engineering and Building Technology; *SHIP HULLS; *ICEBREAKERS; *SHIP MOTION; *SEAKEEPING; *ARCTIC REGIONS; *SEA ICE; NAVY; MOTION; ICE; MATHEMATICAL PREDICTION; MODEL TESTS; SEA STATES; CUTTERS; SHIP BOWS; REAMERS; PREDICTIONS; NAVAL VESSELS; EXPERIMENTAL DATA; FORWARD AREAS; SLAMMING; FREQUENCY; STATIONS; THYSSEN WAAS HULLS; ICE MECHANICS; ARCTIC OCEAN; SMP(SHIP MOTION PROGRAM); FFG-7 VESSEL; LSD-41 VESSEL; MUDYUG VESSEL; PE62121N; Arctic; Arctic Ocean; Ice; Icebreaker; permafrost; Sea ice; ice covered waters
• Online Access: http://www.dtic.mil/docs/citations/ADA243112; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA243112

Conventional naval hull forms allow limited capability in ice covered waters. The potential of the Thyssen-Waas hull form to increase ice breaking effectiveness with a reduction in ice breaking resistance raises possibilities for improving the performance of selected U.S. Navy Ships in arctic regions. It is therefore desirable to investigate the performance of Thyssen-Waas ice transit bow married to selected naval ships. This objective was accomplished in three steps. First, a modification was made to the Navy's Ship Motion Program (SMP) to accurately model the Thyssen-Waas forebody. This was necessary to properly represent the bulges of the reamers/cutters in the bow section. Second, an estimation regarding the quality of the motion predictions was made by comparing the SMP motion predictions with model test data for the Thyssen-Waas icebreaker Mudyug. With satisfactory results from the Mudyug, a seakeeping study was performed of Thyssen-Waas forebodies married to LSD-41 and FFG-7. Numerical predictions indicate the hull forms having a Thyssen-Waas forebody will have less pitch and heave but will slam more frequently in the forward stations than convention naval vessels in higher Sea States. The increase in slamming frequency can be attributed to the flat forebody and shallow stem angle of the Thyssen-Waas bow.