Correct Answer - Option 2 : Kaplan
Explanation:
The specific speed of a turbine is defined as, the speed of a geometrically similar Turbine that would develop unit power when working under a unit head (1m head).
Mathematically it is given by:
\({N_s} = \frac{{N\sqrt P }}{{{H^{\frac{5}{4}}}}}\)
Classification of turbines on the various basis is given in the table below:
|
Flow
|
Energy
|
Head
|
Specific speed
|
Example
|
|
Tangential
|
Impulse
|
High
(300 m and above)
|
Low
(0 – 60 RPM)
|
Pelton Wheel turbine
|
|
Radial
|
Reaction
|
Medium
(30 m to 300 m)
|
Medium
(60 – 300) RPM
|
Francis turbine
|
|
Axial
|
Reaction
|
Low
(less than 30 m)
|
High
|
|
|
(300 – 600) RPM
|
Propeller turbine
|
|
(600 – 1000) RPM
|
Kaplan turbine
|
∴ If the specific speed of the turbine is 300, then the turbine should be Propeller wheel turbine, but in options, the suitable answer will be Kaplan turbine
