calcKristWakeFrac.Rd
Calculate wake fraction (wakeFraction
) (dimensionless)
using the Kristensen method.
calcKristWakeFrac( shipType, breadth, lwl, Cbw, propDiam, M, nProp, tankerBulkCarrierShipTypes = c("tanker", "chemical.tanker", "liquified.gas.tanker", "oil.tanker", "other.tanker", "bulk.carrier") )
shipType | Ship type (vector of strings, see |
---|---|
breadth | Moulded breadth (vector of numericals, m) |
lwl | Waterline length (vector of numericals, m) (see
|
Cbw | Waterline block coefficient (vector of numericals, dimensionless)
(see |
propDiam | Propeller diameter (vector of numericals, m) (see
|
M | Fineness/slenderness coefficient (vector of numericals,
dimensionless) (see |
nProp | Number of propellers (vector of numericals, see
|
tankerBulkCarrierShipTypes | Ship types specified in input
|
wakeFraction
(vector of numericals, dimensionless)
"The speed of advance of the propeller relative to the water in which it is working is lower than the observed speed of the vessel. This difference in speed, expressed as a percentage of the ship speed, is known as the wake fraction coefficient". https://www.wartsila.com/encyclopedia/term/wake-fraction-coefficient
Wake fraction is a component of hull efficiency as well as a component of propeller efficiency.
This method this requires ship types to be grouped. Use the
tankerBulkCarrierShipTypes
grouping parameters to provide these ship
type groupings. Any ship types not included in this grouping will be considered as
miscellaneous vessels.
Kristensen, H. O. and Lutzen, M. 2013. "Prediction of Resistance and Propulsion Power of Ships."
Kristensen, H. O. "Ship-Desmo-Tool." https://gitlab.gbar.dtu.dk/oceanwave3d/Ship-Desmo
Other Kristensen Calculations:
calcKristCaa()
,
calcKristCa()
,
calcKristCr()
,
calcKristPwr()
,
calcKristThrustFactor()
,
calcKristTotalRes()
,
calcKristWettedSA()
calcKristWakeFrac("bulk.carrier",32.25,218.75, 0.8, 6.7,5.2, 1)#> [1] 0.3199536calcKristWakeFrac("oil.tanker",32.25,218.75, 0.8, 6.7,5.2, 1)#> [1] 0.3199536calcKristWakeFrac(c("bulk.carrier","container.ship"), c(32.25,49), c(218.75,400), c(0.8,0.75), c(6.7,9.6), c(5.2,6.7), c(1,1))#> [1] 0.3199536 0.2982483