Some Design Criteria in Basic Ship Design

Transcription

1 Soe Design Criteria in Basic Ship Design Prof. Manuel Ventura Ship Design I MSc in Marine Engineering and Naval Architecture Design Criteria Depending on the type and ission of the ships, during the initial design stage several design criteria can be used to evaluate specific aspects of the ship perforance: Intact Stability Daaged Stability Dynaics Maneuverability Course stability hese criteria can be used either as objective functions of constrains during the ship optiization process Each criterion specifies the relevant variables and the acceptance liits Epirical ethods are presented to deterine soe of the variables at the initial design stage M.Ventura Design Criteria 2 1

2 Intact Stability Criteria for Intact Stability (1) In accordance to IACS (2004) the applicable criteria are: Passenger and cargo ships, of any size, with/without cargo on deck: IMO Res. A.749 (18), Chapters 3.1, 3.2 and 4.1, with the aendents fro MSC Res.75 (69). Offshore supply vessels, of any size: IMO Res. A.749 (18) Chapters 3.2 and 4.5, with the aendents fro MSC Res. 75 (69). Pontoons, of any size : IMO Res A.749 (18) Chapter 4.7 with the aendents fro MSC Res. 75 (69). M.Ventura Design Criteria 4 2

3 Criteria for Intact Stability (2) owing Boats: IMO Res. A.749 (18), Chapter 3.1, with the aendents fro MSC Res. 75 (69), As an alternative, if applicable: IMO Res. A.749 (18), Chapters 4.5, with the aendents fro MSC Res. 75 (69). M.Ventura Design Criteria 5 Criteria for Intact Stability (3) owing boats (cont.) Additionally: he residual area between a righting lever curve and a heeling lever curve developed fro 70% of the axiu bollard pull force acting in 90 to the ship-length direction should not be less than 0,09. he area has to be deterined between the first interception of the two curves and the second interception or the angle of down flooding whichever is less. Alternatively, the area under a righting lever curve should not be less than 1.4 ties the area under a heeling lever curve developed fro 70% of the axiu bollard pull force acting in 90 to ship-length direction. he areas to be deterined between 0 and the 2nd interception or the angle of down flooding whichever is less. M.Ventura Design Criteria 6 3

4 Criteria for Intact Stability (4) owing boats (cont.) he heeling lever curve should be derived by using the following forula: b h = 0.7 H cos Θ/9.81 where: b h = heeling ar [] = axiu bollard pull [kn] H = vertical distance [], between the towing hook and the centre of the propeller = loading condition displaceent [t] M.Ventura Design Criteria 7 Criteria for Intact Stability (5) ypes of ships not included in the IACS recoendation: Fishing vessels Sailing vessels Special purpose vessels, MODUs (Mobile Offshore Drilling Units) Dynaically supported craft Multi-hull craft M.Ventura Design Criteria 8 4

5 IMO A Non-Passenger Ships GZ.dθ ( 0 < θ < 30 ) GZ.dθ ( 0 < θ < 40 ) GZ.dθ (30 < θ < 40 ) GZ ( θ = 30 ) GZ ax GM at angle θ c M.Ventura Design Criteria 9 IMO A.749 Passenger Ships GZ.dθ ( 0 < θ < 30 ) GZ.dθ ( 0 < θ < 40 ) GZ.dθ (30 < θ < 40 ) GZ ( θ = 30 ) GZ ax at an angle θ GM Heel. Angle Max. (passengers at 1 side) Heel. Angle Max. (aneuvering) c M.Ventura Design Criteria 10 5

6 IMO HSC 2000 Stability Criteria he High Speed Craft Code (HSC) includes soe specific stability criteria (IMO Resolution MSC.97(73), 2001) for: Hydrofoil craft (Annex 6) Multi-hull craft (Annex 7) Mono-hull craft (Annex 8) HSC is a craft capable of axiu speed of V ( /s) 3.6 ( ) HSC is applicable to high speed craft engaged in international voyages, either passenger (not ore then 4 hours fro refuge) or cargo (G>500 and not ore than 8 hours fro refuge) at operational speed HSC is not applicable to sailing ships, pleasure craft, fishing ships M.Ventura Design Criteria 11 Intact Stability of Multi-Hull Vessels Cataaran vessels have a difficulty in satisfying the generic requireent of GZax at θ 30 HSC defines GZax at θ 10 for ulti-hull vessels (only for high-speed craft) Japan has suggested a specific intact stability criteria for cataarans (SLF 50/4/6, 2007), which is under discussion, that proposes θ 10 together with soe changes in the other requireents M.Ventura Design Criteria 12 6

7 NES 109 Naval Ships GZ.dθ ( 0 < θ < 30 ) GZ.dθ ( 0 < θ < 40 ) GZ.dθ (30 < θ < 40 ) GZ ( θ = 30 ) GZ ax GZ ax at angle θ GZ ( θ = 0 ) > GM Heeling angle due to Wind < Heeling angle Max. (passengers at 1 side) Heeling angle Max. (aneuver) Angle of extinction of stability c M.Ventura Design Criteria 13 Intact Stability - Epirical Criteria Rahola Criteria (Any Ships) GZ ( θ = 20 ) GZ ( θ = 30 ) θax GZ.dθ ( 0 < θ < θax ) Coastal Ships GM GM < 0.055*B 0.080*B M.Ventura Design Criteria 14 7

8 Criteria Ipleented in AVEVA (1) IMO A167 Intact Stability Criteria IMO 749 Intact Stability Criteria Non Passenger IMO A749 Intact stability Criteria Passenger MARPOL 73/78 (Oil tankers) Load Line (Oil ankers > 150, bulk carriers > 100) PASSENGER Ship Rules (S. I. No. 1216) RO-RO Ship Rules 1990 PASSENGER Ship Rules (One copartent flooding) 1990 PASSENGER Ship Rules (wo or ore cop. flooding) CHEMICAL ANKERS IMO A212 L > 150 NES 109 Intact Stability Criteria NES 109 Daaged Stability Criteria M.Ventura Design Criteria 15 Criteria Ipleented in AVEVA (2) IMO A469 Intact Stability criteria for Offshore Supply Vessels SPECIAL PURPOSE SHIPS IMO A534 USSR 1987 PASSENGER SHIPS GAS CARRIERS Grain criteria Norwegian Fishing Vessel CHEMICAL ANKERS IMO A212 L < 150 NES 109 Intact with ice Geran Ministry of ransport L <= 100 Mobile Offshore Drilling Units MODU Intact Stability Weather Criterion M.Ventura Design Criteria 16 8

9 Daaged Stability Ship Dynaics 9

10 Ship Dynaics Lab and Baxter Period of Roll (Balanço) Cb + B ROLL = B GM Period of Pitch (Cabeceio) Acceptance criteria: B PICH = Cb Cw ROLL 2.0 Period of Heave (Arfage) 2 ( Cb + 0.2) 1.1 ( Cb + 0.2) ( 2.2 D ) ( 1.0 Cb) ( D ) PICH 2.0 HEAVE B Cb PICH HEAVE = Cw HEAVE M.Ventura Design Criteria 19 ROLL