PowerToFroMechChem {afpt} | R Documentation |
Functions convert between mechanical and chemical power
mech2chem(power.mech,bird,...) chem2mech(power.chem,bird,...)
power.mech |
Numerical value for mechanical power |
power.chem |
Numerical value for chemical power |
bird |
object describing the relevant morphological parameters of the bird (or bat); this object should be created using the |
... |
optional arguments (none yet) |
Chemical power is computed as
P.chem = R * (P.mech/eta + BMR)
as described in Pennycuick 2008. Here R is the respiration factor, eta is the muscle conversion efficiency and BMR the basal metabolic rate, see Bird
.
Mechanical power is simply calculated inversely:
P.chem = eta * (P.chem/R - BMR)
Numerical value of either chemical power (mech2chem()
) or mechanical power (chem2mech()
).
Marco Klein Heerenbrink
Pennycuick, C. J. (2008). Modelling the flying bird. Amsterdam, The Netherlands: Elsevier.
## Define a bird: myBird = Bird( massTotal = 0.215, # (kg) total body mass wingSpan = 0.67, # (m) maximum wing span wingArea = 0.0652, # (m2) maximum wing area type = "passerine" ) ## define a speed range speedrange <- seq(5,14,length.out=5) ## compute aerodynamic power for that speed range: Paero <- computeFlappingPower(myBird,speedrange) Pchem <- Paero Pchem$power <- mech2chem(Paero$power,myBird) print(Pchem[c("speed","power","frequency","strokeplane")]) # speed power frequency strokeplane # 1 5.00 15.60151 5.948083 46.56887 # 2 7.25 12.44362 5.948083 31.89129 # 3 9.50 12.79900 5.948083 22.51896 # 4 11.75 15.36721 5.948083 16.49120 # 5 14.00 19.82915 5.948083 12.09174 Pmech <- Pchem Pmech$power <- chem2mech(Pchem$power,myBird) print(Pmech[c("speed","power","frequency","strokeplane")]) # speed power frequency strokeplane # 1 5.00 2.789751 5.948083 46.56887 # 2 7.25 2.129466 5.948083 31.89129 # 3 9.50 2.203773 5.948083 22.51896 # 4 11.75 2.740763 5.948083 16.49120 # 5 14.00 3.673714 5.948083 12.09174