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Q.15 A Kaplan turbine has a runner of diameter
4.0 m. The diameter of the hub is 1.6 m. If the
velocity of flow and the swirl velocity at the
inlet side of the blade at the hub are 6.0 m/s
and 10.0 m/s, respectively, the flow and swirl
velocities at the inlet side of the tip are,
respectively:
(a) 15.0 m/s and 10.0 m/s
(b) 6.0 m/s and 25.0 m/s
(c) 6.0 m/s and 4.0 m/s
(d) 2.5 m/s and 10.0 m/s
[ESE : 2013]​

Answer 1

6.0m/s and 25.m/s Is ur answer

Answer 2

The flow and swirl  velocities at the inlet side of the tip are,  respectively$6.0 m/s$and $4.0 m/s$.

Explanation:

The velocity of flow is constant at every point.

$v_{f}=\frac{Q}{\frac{\pi }{4} (D^{2}-D_{b}^{2})}$

$D_{0}$=runner/ outer diameter

$D_{b}$=hub diameter

$v_{w}_{1}u_{1}=v_{w}_{2}u_{2}$

$v_{w}_{1}=10m/s$

$u_{1}=\frac{\pi *1.6*N}{60}$

$u_{2}=\frac{\pi *4*N}{60}$

$v_{w}_{2}=\frac{10*1.6}{4}$

$=6.0m/s$ and $4.0m/s$.