Priliminary estimation of ship particulars- Double hull Aframax oil tanker

SL NO. IMO_No Ship_Name Registered class Dwt Displacement_Tonnage Speed LBP LOA

1 9232905 Desh bhakht ABS IRS 113913 132663.00 15.10 244.002 9116254 Muroran Maru LR 114106 133563.00 15.50 232.00 243.503 9274616 Pantelis LR 114500 133375.00 15.30 238.99 249.874 9256054 Nevskiy Prospect LR 114597 133280.00 15.10 239.00 249.905 9453975 Paramount Hatteras LR 114700 133412.00 15.50 239.00 249.906 9547673 Atlantico Sul Eas-C-011 LR 114700 133490.00 15.00 239.00 249.007 9467768 Desh Suraksha ABS IRS 114783 136011.00 14.50 249.98 250.008 9331153 Alhani LR 114795 133118.00 14.60 240.70 248.999 9258868 British Swift LR 114809 134583.00 15.70 239.00 251.56

10 9322827 Stena Antarctica LR 114849 133118.00 15.30 239.00 250.0011 9412036 stealth skyros LR 115000 133356.00 15.10 239.00 249.9012 9419357 Iasonas LR 115001 134037.00 14.80 239.00 250.0013 9281009 Everest Spirit LR 115048 133356.00 14.80 239.00 249.9014 9325908 Penelop LR 115091 134511.00 15.10 242.00 253.5015 9383950 Champion Prosperity LR 115098 131630.00 13.00 234.00 243.8016 9402316 Celtic Sea LR 115123 131630.00 14.70 234.00 243.8017 9402328 Kara Sea LR 115191 131630.00 14.70 234.00 243.8018 9378620 Lr2 Polaris LR 115273 131630.00 15.30 235.30 243.8019 9282041 Axel Spirit LR 115392 133601.00 15.30 238.98 249.84

PRELIMINARY ESTIMATION OF PARAMETERS

Displacement

C= DWT/∆For tankers, C is assumed to be 0.86

∆ = (DWT/C) DWT=115000 t ∆ = 133720.930 tonnes

Posdunine's formula,L1= 0.3048*C(V/(2+V))^2*∆^(1/3) V=7.71 m/s

L1= 230.93 m

Schneekluth formula,

L2=V=15kn from statistical data

L2= 242.73 m

from Schneekluth formula,L3= ∆^(0.3)*V^(0.3)*3.2

L3= 248.79 m

Taking the average,

240.82 m

L.O.A displacement=from Volker's Statistics,

L= (∆/1.025)^(1/3)*(3.5+(4.5*V)/(g*(∆/1.025^(1/3))^(1/2)))

L.O.A= 256.40 m

C=0.86

LENGTH BETWEEN PERPENDICULAR (LBP)

C=23.5

∆^(0.3)*V^(0.3)*3.2*((CB+0.5)/(0.145/FN+0.5))CB=0.84 for oil tanker. FN=0.166

LBP=

BreadthB= 10.78*(DWT/1000)^(0.2828)

B= 41.25 m

Depthfor DWT carriers like tankers,

B/D= 1.9recents trends indicate that,

B/D= 1.91 for large tankers

L/D=10 to 14 for tankers so D(MAX) = L/10 = 24.88so D(MIN) = L/14 = 17.20But also

D= B/1.91 = 21.59Taking average

D= 21.2251114805279 m

Draught

for double hull tankersT/D < 0.8

T= 4.536*(DWT/1000)^0.28

T= 17.1264929920754 m

Estimated Ratios

Ratios Values British Swift stealth skyros Penelop Lr2 PolarisL/B 5.84 5.45 5.43 5.50 5.60B/D 1.94 2.06 2.08 2.10 1.96B/T 2.41 2.92 2.97 2.97 2.69T/D 0.81 0.71 0.70 0.70 0.73L/D 11.35 11.22 11.27 11.52 10.94

Froude no: 0.160 0.167 0.160 0.159 0.164

1st iterationL= 239.00 mB= 44 mT= 14.8 mD= 21 m

Froude No.(0.5144)*V/(g*L)^0.5

0.1604

Block Coefficient0.7 +1/(8*atan(25*(0.23-Fn))

0.8192

From Ayre's formula,

C-1.68*Fn C=1.08 for single screw ships

0.8105

also,

1.18-(0.69*V/L^0.5) V= 15 knots L= 783.92 ft

Fn=

Fn=

CB=

CB=

CB=

CB=

CB=

0.8103

and also,

(0.14/Fn)*((L/B+20)/26)

0.8537

From Japanese statistical study

(-4.22+(27.8*Fn^0.5)-(39.1*Fn)+(46.6*Fn^3))0.8345

Taking average and approximating.0.8295

Mass Displacement Volume Displacement∆= 131137.190578 m^3∆= 134415.620 t

Fn= 0.1604Cb=0.8256

Midship Area Coefficient

Cm= 0.9965

Also

1.006-0.0056Cb^(-3.56)Cm= 0.9951

Also

[1+(1-Cb)^(3.5)]^(-1)

CB=

CB=

CB=

CB=CB=

CB=

Cb*L*B*T*ρ*1.006

CM= 0.977+0.085(CB-0.60)

CM=

CM=

0.9980 Am= 649.396463823412 m^2

Average valueCm= 0.9972

Estimation of Bilge RadiusR= (2(1-Cm)B.T/(4-pi))^0.5

2.0480 m considering no rise of floor

Schneekluth's recommendation for bilge radius R,R= B*Ck/((L/B+4)*Cb^2) Ck=0.4-0.7

2.7122 m

Longitudnal Prismatic CoefficientCp= ∆/(1.025*Am*L)Cp= 0.8449

Water Plane Area CoefficientCwp= Cb/(0.471+0.551*Cb)Cwp= 0.8938

Cwp= Cp^(2/3)Cwp= 0.8937 schneekluth 1

Cwp= 0.95*Cp+0.17*(1-Cp)^(1/3) U-hull formCwp= 0.8940

considering the average,Cwp= 0.8938 Awp= 9399.69480314411 m^2

Vertical Prismatic coefficientCvp= ∆/(1.025*Awp*L)Cvp= 0.0584

CM=

Initial checkCm*Cp=Cb

Cm= 0.9972Cp= 0.8449Cb= 0.8295

Cm*Cp= 0.8426

Initial Estimate of Stability

Vertical Centre of Buoyancy, KBKB= T*(1+Cwp)^(-1) for 0.9<CmKB= 7.8148 m

Regression formulations are as follows:KB= T*(0.9-0.36*Cm)

8.0068 m

KB= T*(0.90-0.30*Cm-0.10*Cb)KB= 7.6289 m

KB= T*(0.78-0.285*Cwp)7.7738 m

From Euler's equation,

KB=KB= 7.6765 m

Averaging,KB= 7.69 m

CwT/ (Cw+CB)

Moment of Inertia coefficients, D'Arcangelo

0.1216*Cwp-0.0410

0.0676917923223967

0.350*Cwp^2-0.405*Cwp+0.146

0.0636288205705628

1378135.57528866 m^4 38220842.1977737 m^4

10.77 m 291.46 m

0.810272400891078

10.65 mTaking the average,

10.71 m

291.46 m

Transverse Stability

KG= D*0.63 for tankersKG= 13.23 m

18.40 m

5.17 mconsidering the free surface correction,

Metacentric Radius, BMt and BM L

CIT=

CIT=

CIL=

CIL=

IT= IL=

BMT= BML=

CIT= 0.894´Cw2+0.096

CIT=

BMT= CIT´B2/ (12 TCB)BMT=

BMT=

BML=

KMT= KB+BMt

KMT=

GMT= KMT-KG

GMT=

4.776 m

Longitudinal Stability

291.46 m

MCT 1cm=MCT 1cm= 1599.20 t/cm

Longitudinal Centre of BuoyancyLCB= 9.70-45*Fn+0.8 HarvaldLCB= 3.28 m

LCB is 119.78 m fore of the aft

GM'T= GMT-0.03*KG

GM'T=

GML= BML

GML=

∆*GML/(1.025*100*L)

Beam Depth Draft L/B B/D B/T T/D L/D Froude no:

42.00 21.10 15.00 5.81 1.99 2.80 0.71 11.56 0.15944.04 23.20 15.37 5.27 1.90 2.87 0.66 10.00 0.16743.80 21.30 14.90 5.46 2.06 2.94 0.70 11.22 0.16344.00 21.00 14.80 5.43 2.10 2.97 0.70 11.38 0.16044.03 21.00 14.80 5.43 2.10 2.98 0.70 11.38 0.16543.80 21.00 13.60 5.46 2.09 3.22 0.65 11.38 0.15944.04 21.30 15.12 5.68 2.07 2.91 0.71 11.74 0.15143.84 21.30 14.94 5.49 2.06 2.93 0.70 11.30 0.15543.84 21.30 15.02 5.45 2.06 2.92 0.71 11.22 0.16743.84 21.00 14.94 5.45 2.09 2.93 0.71 11.38 0.16344.03 21.20 14.81 5.43 2.08 2.97 0.70 11.27 0.16044.00 21.00 14.90 5.43 2.10 2.95 0.71 11.38 0.15744.03 21.00 14.82 5.43 2.10 2.97 0.71 11.38 0.15744.00 21.00 14.80 5.50 2.10 2.97 0.70 11.52 0.15942.03 21.50 15.62 5.57 1.95 1.38 0.73 10.88 0.14042.03 21.50 15.62 5.57 1.95 2.69 0.73 10.88 0.15842.04 21.50 15.64 5.57 1.96 2.69 0.73 10.88 0.15842.04 21.50 15.64 5.60 1.96 2.69 0.73 10.94 0.16443.80 21.30 14.93 5.46 2.06 2.93 0.70 11.22 0.163

MEAN 5.50 2.04 2.83 0.70 11.21

from statistical data

130459.4 m^3