Lesson 4.3 Loose Water G B M B1 G2 Z Z2 G3 Z3
CLASS TOPICS 1. Free Surface Effect 2. Example 3. Free Communication 4. Example
FREE SURFACE EFFECT Z G B M B1 G B M B1 G B M B1 G B M B1 G B M B1 G B
FREE SURFACE EFFECT G B M B1 G2 G B M B1 G2 G B M B1 G2 B1 G2 G B M G Z3 Z Z2
B M B1 G G3
B M B1 G G3 GG3
FREE SURFACE EFFECT B3 x L GG3 = 12 x 35 x Wf B = BREADTH OF COMPT L = LENGTH OF COMPT Wf = SHIP'S DISPLACEMENT FREE SURFACE EFFECT = MOMENT OF INERTIA = SHIP'S DISPLACED VOLUME
POCKETING - SHALLOW
POCKETING (NO POCKETING EXISTS)
POCKETING - ALMOST FULL
SURFACE PERMEABILITY
SLUICE VALVES - Closed
SLUICE VALVES - Open
FREE SURFACE EFFECT • Greater with increased length and width of the compartment • Increases as draft decreases (de-ballasting) • Independent of the depth of the liquid • Can be reduced by pocketing
CLASS TOPICS 1. Free Surface Effect 2. Example 3. Free Communication 4. Example
Wo = 3500 Tons 25 FT FWD AFT PORT STBD 4 FT 30 FT FSE?
CLASS TOPICS 1. Free Surface Effect 2. Example 3. Free Communication 4. Example
FREE COMMUNICATION EFFECT FREE COMMUNICATION EFFECT G B M FREE COMMUNICATION EFFECT G B M G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G B M G2 G4 B1 FREE COMMUNICATION EFFECT G5 Z5 G3G5 G3 Z4
FREE COMMUNICATION EFFECT G3G5 = B x L x Y2 35 x Wf B = BREADTH OF COMPT L = LENGTH OF COMPT Y = DIST FM SHIP C/L TO COMPT COG. Wf = SHIP'S DISPLACEMENT FREE COMMUNICATION EFFECT
FREE COMMUNICATION EFFECT COMPARTMENT OPEN TO THE SEA COMPARTMENT PARTIALLY FLOODED COMPARTMENT OFF-CENTERLINE OR ASYMMETRICAL ABOUT THE CENTERLINE
COMPARTMENT OPEN TO SEA COMPARTMENT PARTIALLY FLOODED Y = O NO F.C.E. .
CLASS TOPICS 1. Free Surface Effect 2. Example 3. Free Communication 4. Example