Calculate the density at which the available thrust is equal to the minimum dragby liam1992 Tags: aerodynamics, jet plane, minimum drag, thrust 

#1
Oct3112, 05:23 PM

P: 20

Calculate the density at which the available thrust of a jet propelled aeroplane is equal to the minimum drag for the full fuel load case. Use the simplest assumption for the variation of engine thrust with density.
Wing area, S = 29.5 Weight, W = 88000 C_{D,0} = 0.02 k = 0.044 Max thrust (at sea level) = 16000N C_{T} = 1.7*10^4 I use the formula Dmin = 2((C_{D,0}*k)^0.5)*W = 5221N The problem I have is that I can't work out the density without the velocity but there is no way to relate velocity to drag without density. Where do I go from here? 



#2
Nov112, 07:44 PM

HW Helper
P: 4,714

If you care to revise your posting, supplying the units and explaining what each of the three coefficients is, I'll take a look at your problem.



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