November 2024

  The thrust developed by a propeller is the force it generates to propel the aircraft forward. It depends on the mass of air being accelerated by the propeller and the difference in velocity of the air before and after it passes through the propeller. The formula for thrust is: T=m˙(V∞−V)T = \dot{m} (V_\infty –

Propulsive efficiency (ηp\eta_pηp​) is a measure of how effectively a propulsion system (like a propeller, jet engine, or rocket) converts the energy in the fuel or input energy into useful forward motion of the vehicle. It compares the useful power used to move the vehicle to the total power available from the propulsion system.

The induced drag coefficient (CD,i)(C_{D,i})(CD,i​) is a dimensionless number that represents the drag due to the generation of lift by a wing or other lifting surface. It is caused by the creation of wingtip vortices and the associated downwash, which increases the effective angle of attack of the wing, reducing its ability to produce lift

The drag polar of an airplane relates the drag coefficient (CDC_DCD​) to the lift coefficient (CLC_LCL​). It is expressed as: CD=CD0+kCL2C_D = C_{D0} + kC_L^2CD​=CD0​+kCL2​ Here, CD0C_{D0}CD0​ is the parasite drag coefficient, and kkk is the coefficient of induced drag. To estimate the drag polar, we need to calculate CD0C_{D0}CD0​ and kkk.