calcResistanceShipPwr.Rd
Calculate ship power (kW) for resistance-based power models.
calcResistanceShipPwr( Rtot, shipSpeed, hullEff, openWaterEff, totalInstalledPwr, shaftEff = 0.98, relRotationEff = 1, pwrUpperBoundPercent = 1, pwrLowerBoundPercent = 0.02 )
Rtot | Total ship resistance (vector of numericals, kN) (see
|
---|---|
shipSpeed | Ship actual speed (vector of numericals, m/s) (see
|
hullEff | Hull efficiency (vector of numericals, dimensionless) (see
|
openWaterEff | Open water efficiency (vector of numericals,
dimensionless) (see |
totalInstalledPwr | Total installed main engine power (vector of numericals, kW) (maximum continuous rated power) |
shaftEff | Shaft efficiency (dimensionless). Default = 0.98. Ratio of power delivered to the propeller and the brake power delivered by the engine. Can supply either a vector of numericals, a single number, or rely on the default |
relRotationEff | Relative rotational efficiency (dimensionless). Default = 1. Accounts for effect of rotational flow of water around propeller. Can supply either a vector of numericals, a single number, or rely on the default |
pwrUpperBoundPercent | Percent of total installed power at which
required power is capped (1 indicates required power cannot exceed
|
pwrLowerBoundPercent | Percent of total installed power to act as lower
bound for required power (0.02 indicates required power cannot go below 2%
of |
power (vector of numericals, kW)
This function is called by both Holtrop & Mennen (calcHMPwr
)
and Kristensen (calcKristPwr
) power calculations, where each
uses has its own total resistance calculation (calcHMTotalRes
and calcKristTotalRes
).
Assumptions for shaft efficiency and relative rotational efficiency are based on MAN.
MAN Energy Solutions. 2011. "Basic Principles of Propulsion."
calcResistanceShipPwr(398.487,10.8, 1.191176, 0.721239,9363, shaftEff=0.98,relRotationEff=1)#> [1] 5111.598