Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Thrust in Newtons (aviation)

  1. Nov 7, 2014 #1
    Given that an engine's rated power is 160 HP (~119kW), how can I express thrust (T) in newtons, if aerodynamic drag (D) requires weight expressed in newtons as well to ensure consistency when calculating power available (Pa) and power required (Pr)?:

    [itex]D = (\frac{1}{2}\rho SC_{D})V^{2}+\frac{2W^2}{\rho S\pi AV^2}[/itex]

    where:

    [itex]\rho[/itex] = density at given altitude, [itex]\frac{kg}{m^3}[/itex]
    [itex]S[/itex] = wing area, [itex]m^2[/itex]
    [itex]C_{D}[/itex] = zero-lift coefficient of drag
    [itex]V[/itex] = true airspeed, [itex]\frac{m}{s}[/itex]
    [itex]A[/itex] = wing aspect ratio

    I want to solve the equation for excess power: [itex]P_{ex} = P_{a} - P_{r} = TV - DV[/itex]

    Thank you!

    Rustam
     
  2. jcsd
  3. Nov 8, 2014 #2

    OldEngr63

    User Avatar
    Gold Member

    Power is expressed by the relation
    P = F * V
    where
    P is power,
    F is force (thrust, drag, etc)
    V is velocity (speed)
     
  4. Nov 10, 2014 #3

    cjl

    User Avatar

    Rather than changing the thrust to newtons, why don't you convert the drag force to a power required value? You can do that with the equation mentioned by OldEngr63 above - knowing the drag force at any given speed, you can calculate the power required for level flight. Power available won't be the engine power though, which will complicate things - if you want an accurate result, you should also account for propeller efficiency.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Thrust in Newtons (aviation)
  1. Aviation forum (Replies: 1)

  2. Aviation future (Replies: 30)

  3. Aviation/Jet Fuels (Replies: 17)

Loading...