A crude but useful approximation for an incompressible boundary layer is a cubic variation from u = 0 at the surface (y = δ) to
the freestream velocity, U, at the edge of the boundary layer (y = 0). The equation for the profile is u/U = 3/2(y/δ) – 1/2(y/δ)3, where δ = cx1/2 and c is a constant. Derive the simplest expression for v/U, the y component of velocity ratio. Determine the y/δ location for the maximum value of the ratio v/U. Determine v/U for y = 1 mm, δ = 5 mm and x = 0.87 m. Determine vmax/U for δ = 5 mm and x = 0.87 m.
1 answer:
You might be interested in
Answer:
Q1: 3.2km
Q2: 4.8K
Explanation:
Q1:
So db is the distance of bird, and dr is the distance of runner
db = 2vr and the distance of bird is going to be 2 times greater than the runner.
formulas: db = 2vr & db = 2dr
- db = 2dr
- L + (L - x) = 2x
- 2L - x = 2x
- 2L = 3x
- x =
L
Insert it in x = L
(2.4km) = 1.6km
Now we use formula db = 2dr
- db = 2L - x
- db = 2(2.4km) - 1.6km
- <u>db = 3.2km</u>
Q2:
Formulas: Vr = L /Δt & Vb = db/Δt
- Vr = L/ Δt ⇒ Δt =
(Km cancel each other)
- Vb = db/Δt ⇒ db = VbΔt
- 13.6km/hr
- <u>4.8km</u>
(hr cancel each other)
Hope it helps you :)