Ballast/Dsplacement Ratio

[Antonio Alcalá]

I get it ! Guillermo. I finally did it!

Take a look..

PUMA 34

NAO GLASS ESP

year :75

Polyester


LOA(m):10.35


LWL (m):8.20

Beam (m):3.35


Draught (m):1.85


Sloop Rigged (m2):65.00


weight (t):5.400 kg


ballast (t):2.400 kg

and

FIRST 345

Quillard
Longueur hors tout: 11.00 m
Longueur de coque: 10.55 m
Flottaison: 9.08 m
Maître Bau: 3.49 m
Hauteur sous barrots: 1.92 m
Tirant d'eau: 1.45 ou 2.02 m
Déplacement: 5700 kg
Lest: 2050 kg
Grand-voile: 25.70 m²
Génois: 41.00 m²
Spi: 90.00 m²
Jauge: 10.30 Tx
Catégorie maxi: 1ere
Matériau: Polyester
Construit de: 1984 à 1987
Architecte: Berret
Chantier: Bénéteau
Pays: France


These data are fine, trust me. Source: http://www.voilic.com/#VOILIC


Waiting numbers...

Best Winds

[Guillermo]

Well done Antonio!

FIRST 345

INPUT
Loa = 11,00 m
Lh = 10,55 m
Lwl = 9,08 m
Bmax = 3,49 m
Bwl = 3,14 m
Draught T = 1,45 m
Body draught Tc = 0,57 m (WILD GUESS. Profile missing)
Moulded depth H = 1,75 m (WILD GUESS. Profile missing)
Disp = 5700 kg
Ballast = 2050 kg
Sail area = 50,73 m2
Mast height = 15,01 m
Heeling Arm = 6,58 m
Power = 21 KW

OUTPUTS
Length/Beam Ratio (2Lwl + Lh)/3B = 2,74
Lwl/Bwl Ratio Lwl/Bwl = 2,89
Length/Draught Ratio Lh/T = 7,28
Beam/Draught Ratio Bmax/T = 2,41
WL beam/Body draught Bwl/Tc = 4,69
Ballast/Disp Ratio W/Disp = 0,36
Displacement/Length Ratio D/L = 212,37
Sail Area/Disp. Ratio SA/D = 16,16
Sail Area/Wetted surface SA/WS = 2,05
Power/ Disp. Ratio HP/D = 2,27 HP/ton
Hull speed HSPD = 7,31 Kn
Potential Maximum Speed PMS = 7,90 Kn
Velocity Ratio VR = 1,08
Best motoring speed (1.1) CSPD = 6,00 Kn
Capsize Safety Factor CSF = 1,97
Motion Comfort Ratio MCR = 24,00
Roll Period T = 2,78 Sec
Roll Acceleration Acc = 0,12 G's
Stability Index SI = 0,80
Angle of Vanishing Stability AVS = 120 º
Dellenbaugh Angle DA = 16,13 º (14 kn wind)
Wind pressure coefficient WPC = 1,31

Estimated STIX 38,68

As moulded depth is relevant to calculate STIX, the figure here has to be taken with more care than usual.

NOT TRUSTABLE NUMBERS!

Cheers.

[Guillermo]

Using your numbers for the Puma 34, except for sail area, and guessing a lot:

INPUT
Lh = 10,35 m
Lwl = 8,20 m
Bmax = 3,35 m
Bwl = 3,02 m
Draught T = 1,85 m
Body draught Tc = 0,63 m (WILD GUESS)
Moulded depth H = 1,75 m (WILD GUESS)
Disp = 5400 kg
Ballast = 2400 kg
Sail area = 55 m2 (WILD GUESS)
Mast height = 15.5 m (WILD GUESS)
Heeling Arm = 6.94 m (WILD GUESS)
Power = 13,5 KW


OUTPUT
Length/Beam Ratio (2Lwl + Lh)/3B = 2,66
Lwl/Bwl Ratio Lwl/Bwl = 2,72
Length/Draught Ratio Lh/T = 5,59
Beam/Draught Ratio Bmax/T = 1,81
WL beam/Body draught Bwl/Tc = 4,79
Ballast/Disp Ratio W/Disp = 0,44
Displacement/Length Ratio D/L = 273,17
Sail Area/Disp. Ratio SA/D = 18,16
Sail Area/Wetted surface SA/WS = 2,43
Power/ Disp. Ratio HP/D = 1,54 HP/ton
Hull speed HSPD = 6,95 Kn
Potential Maximum Speed PMS = 7,82 Kn
Velocity Ratio VR = 1,13
Best motoring speed (1.1) CSPD = 5,71 Kn
Capsize Safety Factor CSF = 1,93
Motion Comfort Ratio MCR = 25,85
Roll Period T = 2,96 Sec
Roll Acceleration Acc = 0,10 G's
Stability Index SI = 0,88
Angle of Vanishing Stability AVS = 126 º
Dellenbaugh Angle DA = 24,06 º (14 kn wind)
Wind pressure coefficient WPC = 0,88


Estimated STIX 37,14

The same as before:
NOT TRUSTABLE NUMBERS!

Cheers.