Hydraulic Turbines: Classification and Specific Speeds

Introduction to Hydraulic Turbines

• • Hydraulic turbines convert water energy into mechanical energy.
• • Used in hydropower plants to generate electricity.

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Classification by Energy Conversion

• 1. Impulse Turbine:
• - Converts kinetic energy to mechanical energy
• - Example: Pelton Turbine

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• 2. Reaction Turbine:
• - Converts both kinetic and pressure energy
• - Examples: Francis Turbine, Kaplan Turbine

Classification by Flow Direction

• • Axial Flow Turbine: Water flows parallel (e.g., Kaplan Turbine)
• • Radial Flow Turbine: Water flows perpendicular (e.g., Old Francis Turbine)
• • Mixed Flow Turbine: Combination of both (e.g., Modern Francis Turbine)

KAPLAN

Francis

Modern Francis turbine

Classification by Head and Discharge

• • High-Head (Above 300 m): Pelton Turbine
• • Medium-Head (30-300 m): Francis Turbine
• • Low-Head (Below 30 m): Kaplan Turbine

Specific Speed of Turbines

Specific Speed Ranges and Turbine Types