Answer to Question #229446 in Mechanical Engineering for Pavan

Question

A 20 cm diameter jet of water strikes a curved vane with a velocity of 30 m/s. The inlet vane angle is zero and the outlet angle is 25°. Find the resultant force on the vane

(a) when the vane is fixed;

(b) when the vane is moving with a velocity of 15 m/s in the direction of jet.

Answer 1

when the vane is fixed

$F_n = \rho A(V-u)^2sin\theta$

$F_n = 1000 \times \frac{\pi}{4}(0.2)^2\times 30 \times sin25 = 398.30 N$

when the vane is moving with a velocity of 15 m/s in the direction of jet.

$F_n = \rho A(V+u)^2sin\theta$

$F_n = 1000 \times \frac{\pi}{4}(0.2)^2\times 45 \times sin25 = 597.46 N$