Performance Characteristics of Kaplan Turbine
Objective
To conduct the performance test on kaplan turbine under constant head and to plot the operating characteristics.
Apparatus used:
Kaplan Turbine Setup with Centrifugal Pump, Spring Balance with Weights, etc.
Description Impulse turbine: is a turbine that is driven by high velocity jets of water or steam from a nozzle directed on to vanes or buckets attached to a wheel.
Reaction turbine: is a type of turbine that develops torque by reacting to the pressure or weight of a fluid.
Axial turbine: is a turbine in which the flow of the working fluid is parallel to the shaft, as opposed to radial turbines, where the fluid runs around a shaft, as in a watermill.
Input Power: is the power, which is required by the appliance at its input i.e., from the plug point.
Unit Power: The power dissipated by a current of 1 ampere flowing across a resistance of 1 ohm. kW, kilowatt. a unit of power equal to 1000 watts.
Unit Discharge: is defined as the discharge passing through a turbine, which is working under a unit head
Start the pump by pressing the start button and select the head.
Set the head of water to be constant by rotating the inlet valve.
Constant head (H)=
Apply the weight on the pan and note the torque reading.
Radius of brake drum (R)= 0.15 m
Dead weight of the pan =
Spring balance reading =
Torque, T =
τ (N-m) = (W - S) × R × gNote the speed of the motor by inserting the tachometer.
Speed (N) =
Note the Rectangular notch reading to find the discharge.
Initial reading (water level till crest) = 2.6 cm
Final reading =
Head of water (h) =
Actual discharge, Qact =
Qact (m3/sec) = 2⁄3×Cd× L × √(2g) × H(3/2)- Cd: Co-efficient of discharge: 0.6
- L: Length of the wire = 0.47m
- H: Head over the rectangular notch
Observation
Specific Weight of water (γ) = 9810N/m3
Constant Head (H) =
Actual discharge, Qact =
Speed of motor (N) =
Torque (τ) =
Result
Input power =
Input Power (W) = γ × Qact × HOutput power =
Output Power (W) = (2 × π × N × τ)⁄60Efficiency =
Efficiency (%) = Output Power⁄Input Power× 100Unit power =
Unit power (W) = Output Power⁄(H3/2)Unit speed =
Unit speed (rpm) = N⁄√HUnit discharge =
Unit discharge (m3/sec) = Qact⁄√HCharacteristic Curves
Trial =
Both ends of the pipe must be trimmed to ensure parallel faces.
