- •Contents
- •Preface
- •1. Main dimensions and main ratios
- •1.3 Depth, draught and freeboard
- •1.7 The design equation
- •1.8 References
- •2. Lines design
- •2.1 Statement of the problem
- •2.2 Shape of sectional area curve
- •2.3 Bow and forward section forms
- •2.4 Bulbous bow
- •2.5 Stern forms
- •2.6 Conventional propeller arrangement
- •2.7 Problems of design in broad, shallow-draught ships
- •2.8 Propeller clearances
- •2.9 The conventional method of lines design
- •2.10 Lines design using distortion of existing forms
- •2.12 References
- •3. Optimization in design
- •3.1 Introduction to methodology of optimization
- •3.2 Scope of application in ship design
- •3.3 Economic basics for optimization
- •3.4 Discussion of some important parameters
- •3.5 Special cases of optimization
- •3.6 Developments of the 1980s and 1990s
- •3.7 References
- •4. Some unconventional propulsion arrangements
- •4.1 Rudder propeller
- •4.2 Overlapping propellers
- •4.3 Contra-rotating propellers
- •4.4 Controllable-pitch propellers
- •4.5 Kort nozzles
- •4.6 Further devices to improve propulsion
- •4.7 References
- •5. Computation of weights and centres of mass
- •5.1 Steel weight
- •5.3 Weight of engine plant
- •5.4 Weight margin
- •5.5 References
- •6. Ship propulsion
- •6.1 Interaction between ship and propeller
- •6.2 Power prognosis using the admiralty formula
- •6.3 Ship resistance under trial conditions
- •6.4 Additional resistance under service conditions
- •6.5 References
- •Appendix
- •A.1 Stability regulations
- •References
- •Nomenclature
- •Index
Appendix 213
calculation of stability in heavy seas assumes waves of ship's length moving at the same speed and in the same direction as the ship. Seen from the ship, this gives the impression of a standing wave. Different heeling moments and stability requirementsÐe.g. relating to the inclination achievedÐare specified for the following sea conditions:
1.Ship in calm water.
2.Ship on wave crest.
3.Effectiveness of a lever arm curve determined as the mean value from wave crest and wave trough conditions.
Various load conditions form the basis for all three cases. The navy adopted this method of comparing heeling and righting lever arms on the advice of Wendel (1965) who initiated this approach. The stability review can also be used to improve the safety of cargo ships, although it cannot account for dynamic effects. The approach is especially useful for ships with broad, shallow sterns.
References
ABICHT, W. (1988). Leckstabilitat¨ und Unterteilung. Handbuch der Werften XIX, Hansa, p. 13 ABICHT, W. (1989). New formulas for calculating the probability of compartment flooding in the
case of side damage. Schiffstechnik 36, p. 51
ABICHT, W. (1992). Unterteilung und Leckstabilitat¨ von Frachtschiffen. Handbuch der Werften XXI, Hansa, p. 281
¨ , . (1995). On probabilistic damage stability. Naval Architect, p. E484
BJORKMAN A
GILBERT, R. R. and CARD, J. C. (1990). The new international standard for subdivision and damage stability of dry cargo ships. Marine Technology 27/2, p. 117
IMO (1992). MARPOL 73/78 ÐConsolidated Edition 1991. International Maritime Organization, London
IMO (1995). Code on intact stability for all types of ships covered by IMO instruments. International Maritime Organization, London
IMO (1997). SOLAS ÐConsolidated Edition 1997 International Maritime Organization, London RAHOLA, I. (1939). The Judging of the Stability of Ships. Ph.D. thesis, Helsinki
SBG (1984). Bekanntmachung uber¨ die Anwendung der Stabilitatsvorschriften¨ fur¨ Frachtschiffe, Fahrgastschiffe und Sonderfahrzeuge vom 24. Oktober 1984. Seeberufsgenossenschaft, Hamburg
SEEFISCH, F. (1965). Stabilitatsbeurteilung¨ in der Praxis. Jahrbuch Schiffbautechn. Gesellschaft, Springer, p. 578
SONNENSCHEIN, R. J. and YANG, C. C. (1993). One-compartment damage survivability versus 1992 IMO probabilistic damage criteria for dry cargo ships. Marine Technology 30/1, p. 3
VOGT, K. (1988). Stabilitatsvorschriften¨ fur¨ Schiffe/Boote der Bundeswehr. Handbuch der Werften XIX, Hansa, p. 91
¨
WENDEL, K. (1965). Bemessung und Uberwachung der Stabilitat¨. Jahrbuch Schiffbautechn. Gesellschaft, Springer, p. 609