PERFORMANCE OF THE ZINC ANODE SHAPE DESIGN INSTALLATION ON THE SEABUS ALU-01 FASTSHIP

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ICSOT Indonesia, 4-5 November 2014, Makassar, Indonesia

PERFORMANCE OF THE ZINC ANODE SHAPE DESIGN INSTALLATION ON THE SEABUS ALU-01 FASTSHIP

Neny Praharsiwi Utomo, Ali Munazid, Bagiyo Suwasono, Hang Tuah University, Indonesia SUMMARY

The Seabus Alu-01 ship is an aluminum fast ship type, that has a service speed of 35-45 knots. Installation of the zinc anode on the Seabus Alu-01 is different from any general ship, as the zinc anode is mounted by protuding it into the ship’s hull. This research performed a simulation the ship seabus alu-01 which has been modified to use the elipse zinc anode. The final results of the research showed that elipse zinc anode better than square zinc anode, because the ship using elipse zinc anode has a flow velocities hull faster than ship using square zinc anode, drag force value lower, and the value of force lift ship using elipse zinc anode higher than ship using square zinc anode.

Keywords: Elipse zinc anode, Square zinc anode, Fluent,Force Drag, ANSYS 14.5.

NOMENCLATURE

Bernoulli’s equation states that −dp = d( 12_V 2). By integrating that over the wing surface, and implementing a constant, the following formula can be found:

Where :

Fl : Force lift (N)

Fd : Force Drag (N)

ρ : Density of water(kg/m³) Uatau V : Velocity Fluent (m/s)

Aatau S : Plan View Area (m²) Cl : Coeffisient of Force Lift Cd : Coeffisient of Force Drag

INTRODUCTION

The current increase of people demand on fast ship has given opportunities to the planners, and ship manufacturing companies to manufacture the fast, safe, and reliable operational ships. In addition to the propulsion, the hull shape factor also significantly influences the ship performance. Therefore many ship manufacturing companies have tried to design the ship

hull for maximal performance. The related aspects to the said matters, among others are: the resistance influence, and the fluid flows profile at the ship hull.

As come to our knowledge, any fluid flowing to a material will cause friction. This matter is very damaging, and must be minimized as possible as practicable. One of efforts performed is to modify the shape of the questioned material itself. A ship with less friction becomes the main purpose of the planner, since it means to save the horse power usage, and the more efficient fuel consumption, also the lighter engine weight, so as it may increase ship’s loading capacity.

From the aforesaid matters, it is the duty of a fast ship architect, especially the SEABUS ALU-01 ship, to design a lower friction hull ship while it moves through water. The SEABUS ALU-01 ship is an aluminum fast ship type of PT. Orela Shipyard. The questioned ship is leased by PT. TOTAL PRIME ENGINEERING as to be operated in East Kalimantan waters. The hull design of SEABUS ALU-01 is different from any general ships, as the zinc anode is mounted by protruding it into the ship’s hull. The process is initialized with the manufacturing of aluminum plat 5083 bowl construction adjusting to the zinc anode dimension (use beam zinc anode of S4 type). After making the hole

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at the ship’s bottom with aluminum (bowl) construction to be used, nut the zinc anodewith the prepared aluminum (bowl) construction, the last process of hull shape design of the SEABUS ALU-01 ship is the assembly process, where the zinc anode construction series (zinc anode with aluminum construction) are to be welded at its bottom part with protruded construction into the ship hull (holed first), so as the zinc anod almost flat with the ship hull. However, it is still considered as less appropriate to maximize the ship performance. Therefore, the Planning Department of PT.

ORELA SHIPYARD offers to modify the aluminum construction and zinc anode shapes from beam (

to ellipse shape (type E3).

Fig. 1. Zinc Anode Conditions on Seabus Alu Upon the aforesaid case study, this study focus on the most appropriate Zinc anode shape

Mounting Performance for SEABUS ALU 01 fast ship.

RESULT AND CALCULATION

Data obtained from the ships’ SEABUS ALU 01 as well as the design and the shape of the

used on the SEABUS ALU 01

The data ship's of SEABUS ALU 01

The dimensions of a ship's model used in this research are as follows

- Length Over All (LOA) : 11 m

- Length (Lpp) : 9,9 m

- Waterline Length : 8,9 m

- (moulded-B) : 3 m

- (moulded-T) : 3 m

5 November 2014, Makassar, Indonesia

Institution of Naval Architects at the ship’s bottom with aluminum (bowl) construction to be used, nut the zinc anodewith the prepared aluminum (bowl) construction, the last process of hull 01 ship is the assembly process, where the zinc anode construction series (zinc anode with aluminum construction) are to be welded at its bottom part with protruded construction into the ship hull (holed first), so as the zinc anode is almost flat with the ship hull. However, it is still considered as less appropriate to maximize the ship performance. Therefore, the Planning Department of PT.

ORELA SHIPYARD offers to modify the aluminum construction and zinc anode shapes from beam (S4 type)

Fig. 1. Zinc Anode Conditions on Seabus Alu-01 Upon the aforesaid case study, this study focus

Zinc anode shape design Performance for SEABUS ALU 01 fast ship.

CALCULATION

SEABUS ALU 01 as well as the design and the shape of the zinc anode

The dimensions of a ship's model used in this

- Draught (T) : 0,5 m

- Cruising Speed : 35-

- Passenggers : 9 orang

- Crew : 2 crew

The shape and dimensions of the zinc anode

1. Mod. Square (S4): the shape of the zinc anode with the size (220 x 130 x 30)

Fig.2.Zinc Anode model's 1 (type S4)

2. Mod. Elipse (E3): the shape of the zinc anode with the size (220 x 130 x 30)

Fig. 3. Zinc Anode model's 2 (type E3) Simulation Ship’s Model

1. Ship’s Model l: this model was selected as a comparison or baseline, with a simple form to facilitate the process of modeling.

Fig. 4. Ship’s Model 1 Without Installation of Anode

: 0,5 m - 45 knot : 9 orang : 2 crew

zinc anode Mod. Square (S4): the shape of the zinc anode with

Fig.2.Zinc Anode model's 1 (type S4)

shape of the zinc anode with

Fig. 3. Zinc Anode model's 2 (type E3)

Ship’s Model l: this model was selected as a comparison or baseline, with a simple form to facilitate the process of modeling.

Installation of Zinc

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2. Ship’s Model II : model of ship by using elliptical anodes tumbal (type E3). This ship’s model is a modification of the installation of the square zinc anode becoming elips.

Fig. 5. Ship’s model (ship using elipse zinc anodes

3. Ship Model III: model ship using type box

anode tumbal (S4). This ship's model is a model used square zinc anode (type S4) on the SEABUS ALU 01 fast ship now.

Fig. 6. Ship’s model (ship using square zinc anodes The Seabus Alu-01 ships flow

using elipse zinc anode at a speed 25 knots and 45 knots

Fig. 7. Result of Fluent’s Streamline Ship’s Model II 5 November 2014, Makassar, Indonesia

Institution of Naval Architects Ship’s Model II : model of ship by using elliptical anodes tumbal (type E3). This ship’s model is a modification of the installation of the square zinc anode becoming elips.

model II anodes type E3)

III: model ship using type box-shaped anode tumbal (S4). This ship's model is a model used square zinc anode (type S4) on the SEABUS

model III anodes type S4)

01 ships flow simulation results using elipse zinc anode at a speed 25 knots and 45

Fig. 7. Result of Fluent’s Streamline Ship’s Model II

The Seabus Alu-01 ships flow simulation results using square zinc anode at a speed 25 knots and 45 knots

Fig. 8. Result of Fluent’s Streamline Ship’s Model II Table 1. Velocity Streamline

25 knot elips

45 knot elips

11.69 m/s 14,49 m/s 11,83 23,13 m/s 29,60 m/s 23,07 17,41 m/s 22,36 m/s 17,45

From the depiction of the model until process simulation is carried out, then the obtained data after search is as follows

Data simulated results

variation of speed. The results obtained the simulation process taken a variation of experiments that have been done are

Comparison of speed with of 3 ships

From the above curve shows that on a variety of low-speed drag force value does not experience the

-10.000 0.000 10.000 20.000 30.000 40.000 50.000 60.000

0

FdDrag (N)

Speeds (knot)

Simulation result Data Force Drag ships with variations of the speed

01 ships flow simulation results using square zinc anode at a speed 25 knots and 45

Fig. 8. Result of Fluent’s Streamline Ship’s Model II 25 knot

square

25 knot square 11,83 m/s 13,02 m/s 23,07 m/s 27,04 m/s 17,45 m/s 20,36 m/s From the depiction of the model until process simulation is carried out, then the obtained data

results Ship’s Force Drag usinga The results obtained from a variation of the done are the following.

speed with the Force Drag models

From the above curve shows that on a variety of speed drag force value does not experience the

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Simulation result Data Force Drag ships with variations of the speed

ship's model I without installation of zinc anode Ship's model II (ship using elipse zinc anode)

ship's model III (ship using square zinc anode)

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10.000 20.000 30.000 40.000 50.000

0 20 40 60

forcelift (N)

speeds (knots)

Simulation result Data Force Lift ships with variations of the speed

ship model I (ship without installation zinc anode) ship's model II (ship using elipse zinc anode) ship's model III (ship using square zinc anode)

difference that is far enough away, but on the high kecepatan the difference between the three of them became a drag force gets bigger. Starts from 25 knots of speed difference between the drag force ship's model II against the ship’s model I which is 2,467 N. While the value of force drag ship's model III against ship's model I reach 3,186 N. Then at a speed of 35 knots drag force ship's model II against ship's model 1 is 3,166 N.

whereas the difference in ship's model III against ship's model I reach 4,551 N. Next on the maximum speed of 45 knots, the difference between the value of force drag ship's model II against ship's model I namely 5,794 N.

While the ship's model III against ship's model I reached 7,699 N. It can be seen that the value of drag force ship's model II is lower than ship's model III. This is due to the presence of a modified model factor anode used on hull the seabus alu-01, the shape of the square to be ellipse.

Where the surface of the hull the ship's model III wider i.e. 25,22 ݉^ଶcompared to the ship's model II i.e. 23,54

݉^ଶ. Whereas the surface area of the ship's model I just 21,49 ݉^ଶwhich resulted in a laminar flow at the surface more quickly regardless. and turbulent flow at the hull surface will reduced, as well as will reduce the drag force or resistance.

Data simulated results Ship’s Force Liftusing a variation of speed

Comparison of speed with the Force Lift of 3 ship’s models

From the above curve shows that on a variety of low-speed lift force value does not experience the difference that is far enough away, but on the high kecepatan the difference between the three of them became a lift force gets bigger. Starts from 25 knots of speed difference between the lift force ship's model II against the ship’s model I which is 2,467 N. While the value of force lift ship's model III against ship's model I reach 3,186 N. Then at a speed of 35 knots lift force ship's model II against ship's model 1 is 3,166 N.

whereas the difference in ship's model III against ship's model I reach 4,551 N. Next on the maximum speed of 45 knots, the difference between the value of force lift ship's model II against ship's model I namely 5,794N.

While the ship's model III against ship's model I reached 7,699 N. It can be seen that the value of lift force ship's model II is highest than ship's model III. This is due to the presence of a modified model factor anode used on hull the seabus alu-01, the shape of the square to be ellipse. Where the surface of the hull the ship's model III wider i.e. 25,22 ݉^ଶcompared to the ship's model II i.e.

23,54 ݉^ଶ. Whereas the surface area of the ship's model I just 21,49 ݉^ଶwhich resulted in a laminar flow at the surface more quickly regardless, and turbulent flow at the hull surface will reduced, as well as will reduce the drag force or ressistant.

CONCLUSION

From the results of the research it can be concluded that in general the installation of zinc anode are indented or perforated on the SEABUS ALU 01 design forms the square zinc anode (type S4) and modified into the elipse zinc anode (type E3) there is an impact on the performance of the SEABUS Boats ALU 01. Mounting modifications where design forms the elipse zinc anode has a lower shear force compared with the design forms the square zinc anode (ANSYS simulation results 14.5.) it is attested from sliding style

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© 2014: The Royal Institution of Naval Architects of ship model II (elipse zinc anode) on the maximum speed of 45 knots of 54,748 N is lower than the model III (square zinc anode) i.e. 56,637 N. as well as ship model II (elipse zinc anode) on the maximum speed of 45 knots have the lift reaches the 37,121 N (ship using elipse zinc anode) which is only 34,413 N, it means the lift ship the SEABUS ALU 01elipse zinc anode with higher than the square zinc anode.

REFERENCES

Comstock, Jhon. P. (ed) “Priciple of Naval Architecture, The Society of Naval Architect and Marine Engineer”, New York (1967).

http://aerostudents.com/files/introductionToAerospaceEn gineering/introductionToAerospaceEngineeringFullVersi on.pdf

Tuakia, Firman. “The basic of CFD using Fluent Informatika”. Bandung (2008).

McPhail, Steven, Autosub6000: A Deep Diving Long Range AUV. Underwater Systems Laboratory, National Marine Facilities Division National Oceanography Centre, Southampton European Way, Southampton, SO14 3ZH, UK. (2003)

AUTHORS’ BIOGRAPHY

Neny Praharsiwi Utomo was born in Probolinggo, east java, October 13 ^th1991. after solves study at TarunaDra Zulaeha elementary school Surabaya year 2004, then continue study at TarunaDra Zulaeha junior high school Surabaya year 2007, then continue TarunaDra Zulaeha senior high school year 2010 Surabaya then drawns out higher education at hang tuah Surabaya's University Naval Architecture and Ship Building Engineering until now.

Ali Munazid was born at Gresik city on August 19^th,1979. After graduated from Naval Architecture and Ship building Engineering at Hang Tuah University he continuing his study at Sepuluh Nopember Technology

Institute. Now he return to Hang Tuah University as a secretary in Naval Architecture and Ship building Engineering department and also as a lecturer at Hang Tuah University until now.

Bagiyo Suwasono was born in Surabaya, east java, June 23^th 1970. after solves study at 4 senior high school Surabaya Year 1990. then drawns out higher education at hang tuah surabaya's university naval architecture and ship building engineering on year 1990. then solves study at tiered 1 UHT on month of 1995 and direct teaches to become naval architecture and ship engineering regular lecturers UHT 1995 drawns out study at postgraduate ITS and solves study S2 of year 1999. And drawns out study at postgraduate ITS and solves study S3 of year 2011 return to UHT to drawn out career as lecturer of UHT' naval architecture and ship engineering, jam it also conjunct on planning bureau unit of work development and UHT' information system thus far.