TEKNIK PERMESINAN KAPAL II

ME091313 ( 4 SKS)

Jurusan Teknik Sistem Perkapalan

ITS Surabaya

Ship Design

EFFECTIVEit must meet the owner's needs as laid down in the ship requirements. (Capacity and size; Cargo handling; Influence of nature of goods carried; Speed; Maneuverability; Machinery etc.)

EFFICIENTIt must carry out its functions reliably and economically.(Economy; Availability)

SAFE It must be able to operate under the expected conditions without incident and to survive more extreme conditions and accidents within an agreed level of risk.

The Design Process FEASIBILITY STUDIES

The aim at the feasibility stage is to confirm that a design to meet the requirements is possible with the existing technology and to a size and cost likely to be acceptable to the owner.

CONTRACT DESIGNOnce the owner has agreed to the general size and character of the ship more detailed designing can go on. The contract design, as its name implies, is produced to a level that it can be used to order the ship from a shipbuilder, or for a contract price to be quoted. At this stage all major features of the ship will be fixed.

FULL DESIGN

The detailing of the design can now proceed leading to the drawings, which are needed by the production department to build the ship.

CRITERIA FOR CHOOSING THE MAIN ENGINE

Required horsepowerWeightSpaceCapital costRunning costsThe ship’s requirement for electrical power and heatReliability and maintainabilityThe ship’s requirement for maneuvering ability and/or for slow-speed operationEase of installationVibrationNoise and other signaturesAvailability

Required Horsepower

VsVs

RT

T : Thrust(Gaya Dorong)

THP DHP SHP BHP

EHP

EHP : Effective Horse Power

THP : Thrust Horse Power

DHP : Delivered Horse Power

SHP : Shaft Horse Power

BHP : Brake Horse Power

EHP : the power we would have to use to tow the ship without 　propulsive system

THP : the power produced by the propeller’s thrust

Required Horsepower

VsVs

RT

DHPTHP BHPSHP

EHP

Gs

PC

G = SHP / BHPGear Efficiency

s = DHP / SHPShaft Efficiency

PC = EHP / DHPPropulsive Coefficient

EHP = Vs x RT

EHP : kWVs : m/sRT : kN

THP = VA x T

= H x O x R

Required Horsepower Type of propulsion Number of propulsion

Weight & SpaceAs far as the main engines are concerned space and weight generally go together, but if a trade-off between weight and space is possible, then ships designed on a deadweight basis should be fitted with the lighter machinery, even if this takes more space, whilst those designed on a volume basis should be fitted with the less bulky machinery even if this is heavier.

In the design of warships, planning craft and catamarans, the need for a high speed from a relatively small ship makes the power/weight ratio a matter of vital importance.

On warships space, like weight, is at a premium and the power/volume ratio is very important.

Capital and Running Cost The cost of the main engine and the systems The most important item of running costs is

the annual fuel bill

Two fundamentally different ways of minimizing expenditure on fuel:(i) by fitting as fuel efficient an engine as possible even if this requires a relatively expensive fuel; or(ii) by the use of machinery which can burn a cheap fuel even if its specific consumption is comparatively high

The ship’s requirement for electrical power and heat

Because the main engine will generally be able to burn a cheaper fuel than is required by the generators, the use of the main engine(s) to provide electrical energy and/or heat for engine auxiliary plant and hotel services via shaft driven alternator(s) and exhaust gas boiler(s) respectively can have an important influence on running costs.

Diesel Engine Gas Turbine Steam Turbine

ALTERNATIVE MAIN ENGINE TYPES

Diesel Engine

Low Speed

60 – 150

Medium Speed

450 – 800

High Speed

1000 - 3000

Ex. 7000 kW

100 rpm

31 7 tonnes

285 m3

7650 kW

520 rpm

153 tonnes

191 m3

7000 kW

1300 rpm

21 tonnes

40 m3

Power

Up to

97,300 kW

1080MC B&W

23,450 kW

18 V PC 4.2

Pielstick

8,200 kW

V20 M.T.U

SFOC

g/kWh

174 down to 156 200 down to 167 250 down to 187

Low-speed diesel machinery arrangement

Medium-speed diesel machinery arrangement

COGOG CODOG CODAG CODAG