Table of Contents
➤ The Pelton wheel, or Pelton turbine, is an impulse-type water turbine designed by Lester Allan Pelton in the 1870s. It revolutionized hydropower technology by efficiently harnessing energy from the impulse of moving water.
Summary of Pelton Turbine:
Aspect | Information |
Inventor |
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Invention Year |
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First Installation |
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Patent Date |
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Manufacturer |
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Applications |
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Design Principle |
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Operating Principle |
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Efficiency |
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History:
I. Invention and Development:
➤ Lester Allan Pelton, born in 1829, developed the Pelton wheel to address the inefficiencies of existing water turbines.
➤ He patented his invention in October 1880 after successfully building a wooden prototype in the mid-1870s.
➤ The first commercial Pelton Wheel was installed in the Mayflower Mine in Nevada City in 1878.
II. Commercialization:
➤ Pelton’s invention gained widespread recognition for its efficiency, leading to high demand.
➤ The Pelton Water Wheel Company was established in San Francisco in 1888 after Pelton sold the rights and patents.
➤ Over 11,000 turbines were used by 1900, and the company expanded its operations.
III. Company Changes:
➤ In 1956, the Baldwin-Lima-Hamilton Company acquired the Pelton Water Wheel Company, eventually ceasing Pelton wheel manufacturing.
Design:
I. Operational Principle:
➤ The Pelton wheel operates on the principle of extracting energy from the impulse of high-speed water jets.
➤ Nozzles direct forceful streams of water against spoon-shaped buckets (impulse blades) on the wheel’s rim.
II. Efficiency:
➤ Pelton’s design minimizes the speed of water as it leaves the wheel, extracting nearly all impulse energy for high efficiency.
III. Bucket Configuration:
➤ Typically, two buckets are mounted side by side on the wheel, with the water jet split into two streams for balance.
Applications:
- Hydroelectric Power:
➤ Pelton wheels are preferred for hydroelectric power in locations with high hydraulic heads at low flow rates.
➤ They come in various sizes, from small units for mountain streams to large-scale installations like the Bieudron Hydroelectric Power Station in Switzerland.
Design Rules:
- Specific Speed:
➤ The specific speed parameter is crucial for matching hydroelectric sites with the optimal turbine type.
➤ Pelton wheels have a low specific speed, making them suitable for applications with high hydraulic heads.
Turbine Physics and Derivation:
- Optimal Wheel Speed:
➤ The optimal runner speed is when the wheel extracts all kinetic energy from the jet, resulting in a specific relationship with the initial jet velocity.
- Efficiency:
➤ The turbine efficiency is calculated based on wheel power and initial jet power, indicating the efficiency of the nozzle and wheel.
System Components:
- Penstock:
➤ The penstock is the conduit bringing high-pressure water to the Pelton wheel.
➤ Originally referring to the valve, the term now includes all fluid supply hydraulics.
➤ In summary, the Pelton wheel’s design and efficiency make it convenient for harnessing hydropower in situations with high hydraulic heads and low flow rates. Its historical significance lies in revolutionizing water turbine technology and contributing to the development of hydroelectric power systems.