COMPUTER SIMULATIONS ON THE DYNAMIC TENSIONS OF THE EMERGENCY TOWING LINES OF TANKERS IN THE SEAS
This paper concentrates on the dynamic tensions on towlines during the towing operations of tankers by tug boats. Three tankers of 20 000dwt, 100 000dwt and 200 000dwt respectively and two tugs of different pulling capacity of 100 kN and 400 kN respectively were considered for the towing operation. The important towing parameters such as line length and tow speed are mainly decided based on the sea condition. Motion response of a tug and tanker connected by a towline is determined through numerical simulation. The excitations of the tanker and tug are considered treating the towline as a spring. As the size of the tanker is large in comparison to the tug, the excitations of the tug are dominant. Using the determined tension values for various sea states defined by Beaufort scales, typical cases of stability of tugs during the tow operation are calculated. Both low and high frequency motions of the surface vessels are accommodated in the computer simulation, but the inertia force of the towline is neglected. The wave exciting forces, drag of towed vessels and the line tensions govern the system dynamics. Towline tensions in irregular seas are also determined.
-
Supplemental Notes:
- STAB 94, 5th Intl Conf on Stability of Ships and Ocean Vehicles; 7-11 Nov 1994; Florida, USA. Sponsored by SNAME, USA and RINA, UK. Proc. Publ by Florida Inst Technology, USA. Vol 4, session 17 [22 p, 15 ref, 3 tab, 12 fig]
-
Authors:
- INOUE, Y
- Surendran, S
- SHIMIZU, T
- Publication Date: 1994
Language
- English
Subject/Index Terms
- TRT Terms: Cables; Ocean going tugs; Simulation; Tension; Towing devices
- Old TRIS Terms: Ocean towing; Towing cables
- Subject Areas: Marine Transportation; Vehicles and Equipment;
Filing Info
- Accession Number: 00717509
- Record Type: Publication
- Source Agency: British Maritime Technology
- Files: TRIS
- Created Date: Mar 4 1996 12:00AM