Difference between revisions of "TrueWind"
(→calculate True Wind from Apparent Wind) |
(→calculate True Wind from Apparent Wind) |
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** <b>SET</b> Current Set (relative to true north) <b>environment.current.setTrue</b> | ** <b>SET</b> Current Set (relative to true north) <b>environment.current.setTrue</b> | ||
** <code>SET = ATAN ( DFTx / DFTy )</code> | ** <code>SET = ATAN ( DFTx / DFTy )</code> | ||
+ | |||
+ | == simplified, assuming H=COG == | ||
+ | * <b>COG</b> Course Over Ground <b>navigation.courseOverGroundTrue</b> | ||
+ | * <b>AWA</b> Apparent Wind Angle (relative to H) <b>environment.wind.angleApparent</b> | ||
+ | * <b>AWS</b> Apparent Wind Speed <b>environment.wind.speedApparent</b> | ||
+ | ** <b>TWA</b> True Wind Angle (relative to H=COG) <b>environment.wind.angleTrueGround</b> | ||
+ | ** <code>...</code> | ||
+ | ** <b>TWS</b> True Wind Speed (relative to ground) <b>environment.wind.speedOverGround</b> | ||
+ | ** <code>...</code> | ||
== see also == | == see also == |
Revision as of 17:28, 29 October 2018
calculate True Wind from Apparent Wind
- AWA Apparent Wind Angle (relative to H) environment.wind.angleApparent
- H Heading (relative to true north) navigation.headingTrue
- AWD Apparent Wind Direction (relative to true north) environment.wind.directionTrue
AWD = MOD(H+AWA;360)
- AWS Apparent Wind Speed environment.wind.speedApparent
- COG Course Over Ground navigation.courseOverGroundTrue
- SOG Speed Over Ground navigation.speedOverGround
- TWS True Wind Speed (relative to ground) environment.wind.speedOverGround
TWSx = SOG * Sin (COG) - AWS * Sin (AWD)
TWSy = SOG * Cos (COG) - AWS * Cos (AWD)
TWS= SQRT (TWSx*TWSx + TWSy*TWSy)
- TWD True Wind Direction (relative to true north) ???
TWD = ATAN ( TWSx / TWSy )
- STW Speed Trough Water navigation.speedThroughWater
- DFT Current Drift (relative to ground) environment.current.drift
DFTx = SOG * Sin (COG) - STW * Sin (H)
DFTy = SOG * Cos (COG) - STW * Cos (H)
DFT= SQRT (DFTx*DFTx + DFTy*DFTy)
- SET Current Set (relative to true north) environment.current.setTrue
SET = ATAN ( DFTx / DFTy )
simplified, assuming H=COG
- COG Course Over Ground navigation.courseOverGroundTrue
- AWA Apparent Wind Angle (relative to H) environment.wind.angleApparent
- AWS Apparent Wind Speed environment.wind.speedApparent
- TWA True Wind Angle (relative to H=COG) environment.wind.angleTrueGround
...
- TWS True Wind Speed (relative to ground) environment.wind.speedOverGround
...