shipHydrostatics.Tools Namespace Reference

Classes
class  Point

Functions
def areas (ship, n, draft=None, roll=Units.parseQuantity("0 deg"), trim=Units.parseQuantity("0 deg"))
def BMT (ship, draft=None, trim=Units.parseQuantity("0 deg"))
def displacement (ship, draft=None, roll=Units.parseQuantity("0 deg"), trim=Units.parseQuantity("0 deg"))
def floatingArea (ship, draft=None, roll=Units.parseQuantity("0 deg"), trim=Units.parseQuantity("0 deg"))
def getUnderwaterSide (shape, force=True)
def mainFrameCoeff (ship, draft=None)
def moment (ship, draft=None, roll=Units.parseQuantity("0 deg"), trim=Units.parseQuantity("0 deg"))
def placeShipShape (shape, draft, roll, trim)
def wettedArea (shape, draft, roll=Units.parseQuantity("0 deg"), trim=Units.parseQuantity("0 deg"))

Variables
int COMMON_BOOLEAN_ITERATIONS = 10
DENS = Units.parseQuantity("1025 kg/m^3")

Function Documentation

areas()

def shipHydrostatics.Tools.areas	(		ship,
			n,
			draft = None,
			roll = Units.parseQuantity("0 deg"),
			trim = Units.parseQuantity("0 deg")
	)

Compute the ship transversal areas Position arguments: ship -- Ship object (see createShip) n -- Number of points to compute Keyword arguments: draft -- Ship draft (Design ship draft by default) roll -- Roll angle (0 degrees by default) trim -- Trim angle (0 degrees by default) Returned value: List of sections, each section contains 2 values, the x longitudinal coordinate, and the transversal area. If n < 2, an empty list will be returned.

References shipHydrostatics.Tools.getUnderwaterSide(), and shipHydrostatics.Tools.placeShipShape().

BMT()

def shipHydrostatics.Tools.BMT	(		ship,
			draft = None,
			trim = Units.parseQuantity("0 deg")
	)

Calculate "ship Bouyance center" - "transversal metacenter" radius Position arguments: ship -- Ship object (see createShip) Keyword arguments: draft -- Ship draft (Design ship draft by default) trim -- Trim angle (0 degrees by default) Returned value: BMT radius

References shipHydrostatics.Tools.displacement().

displacement()

def shipHydrostatics.Tools.displacement	(		ship,
			draft = None,
			roll = Units.parseQuantity("0 deg"),
			trim = Units.parseQuantity("0 deg")
	)

Compute the ship displacement Position arguments: ship -- Ship object (see createShip) Keyword arguments: draft -- Ship draft (Design ship draft by default) roll -- Roll angle (0 degrees by default) trim -- Trim angle (0 degrees by default) Returned values: disp -- The ship displacement (a density of the water of 1025 kg/m^3 is assumed) B -- Bouyance application point, i.e. Center of mass of the underwater side Cb -- Block coefficient The Bouyance center is referred to the original ship position.

References shipHydrostatics.Tools.getUnderwaterSide(), and shipHydrostatics.Tools.placeShipShape().

Referenced by shipHydrostatics.Tools.BMT(), and shipHydrostatics.Tools.moment().

floatingArea()

def shipHydrostatics.Tools.floatingArea	(		ship,
			draft = None,
			roll = Units.parseQuantity("0 deg"),
			trim = Units.parseQuantity("0 deg")
	)

Compute the ship floating area Position arguments: ship -- Ship object (see createShip) Keyword arguments: draft -- Ship draft (Design ship draft by default) roll -- Roll angle (0 degrees by default) trim -- Trim angle (0 degrees by default) Returned values: area -- Ship floating area cf -- Floating area coefficient

References shipHydrostatics.Tools.placeShipShape().

getUnderwaterSide()

def shipHydrostatics.Tools.getUnderwaterSide	(		shape,
			force = True
	)

Get the underwater shape, simply cropping the provided shape by the z=0 free surface plane. Position arguments: shape -- Solid shape to be cropped Keyword arguments: force -- True if in case the common boolean operation fails, i.e. returns no solids, the tool should retry it slightly moving the free surface. False otherwise. (True by default) Returned value: Cropped shape. It is not modifying the input shape

Referenced by shipHydrostatics.Tools.areas(), shipHydrostatics.Tools.displacement(), shipHydrostatics.Tools.mainFrameCoeff(), and shipHydrostatics.Tools.wettedArea().

mainFrameCoeff()

def shipHydrostatics.Tools.mainFrameCoeff	(		ship,
			draft = None
	)

Compute the main frame coefficient Position arguments: ship -- Ship object (see createShip) Keyword arguments: draft -- Ship draft (Design ship draft by default) Returned value: Ship main frame area coefficient

References shipHydrostatics.Tools.getUnderwaterSide(), and shipHydrostatics.Tools.placeShipShape().

moment()

def shipHydrostatics.Tools.moment	(		ship,
			draft = None,
			roll = Units.parseQuantity("0 deg"),
			trim = Units.parseQuantity("0 deg")
	)

Compute the moment required to trim the ship 1cm Position arguments: ship -- Ship object (see createShip) Keyword arguments: draft -- Ship draft (Design ship draft by default) roll -- Roll angle (0 degrees by default) trim -- Trim angle (0 degrees by default) Returned value: Moment required to trim the ship 1cm. Such moment is positive if it cause a positive trim angle. The moment is expressed as a mass by a distance, not as a force by a distance

References shipHydrostatics.Tools.displacement().

placeShipShape()

def shipHydrostatics.Tools.placeShipShape	(		shape,
			draft,
			roll,
			trim
	)

Move the ship shape such that the free surface matches with the plane z=0. The transformation will be applied on the input shape, so copy it before calling this method if it should be preserved. Position arguments: shape -- Ship shape draft -- Ship draft roll -- Roll angle trim -- Trim angle Returned values: shape -- The same transformed input shape. Just for debugging purposes, you can discard it. base_z -- The new base z coordinate (after applying the roll angle). Useful if you want to revert back the transformation

Referenced by shipHydrostatics.Tools.areas(), shipHydrostatics.Tools.displacement(), shipHydrostatics.Tools.floatingArea(), shipHydrostatics.Tools.mainFrameCoeff(), and shipHydrostatics.Tools.wettedArea().

wettedArea()

def shipHydrostatics.Tools.wettedArea	(		shape,
			draft,
			roll = Units.parseQuantity("0 deg"),
			trim = Units.parseQuantity("0 deg")
	)

Compute the ship wetted area Position arguments: shape -- External faces of the ship hull draft -- Ship draft Keyword arguments: roll -- Roll angle (0 degrees by default) trim -- Trim angle (0 degrees by default) Returned value: The wetted area, i.e. The underwater side area

References shipHydrostatics.Tools.getUnderwaterSide(), and shipHydrostatics.Tools.placeShipShape().

Variable Documentation

COMMON_BOOLEAN_ITERATIONS

int shipHydrostatics.Tools.COMMON_BOOLEAN_ITERATIONS = 10

DENS

shipHydrostatics.Tools.DENS = Units.parseQuantity("1025 kg/m^3")