The Turbine Suitable for Low Heads and High Flow Rates is Kaplan Turbine. Let's understand why:

Kaplan Turbine:

- A Kaplan turbine is a type of propeller turbine that is suitable for low head and high flow rates.
- It is an axial flow turbine that has adjustable blades to optimize its performance for different operating conditions.
- The blades are typically made of stainless steel or a composite material to withstand the high water velocities and pressures.
- It operates with a high efficiency over a wide range of flow rates and heads, making it a popular choice for hydroelectric power generation.
- The Kaplan turbine is used in power plants with a head of less than 30 meters and a flow rate of up to 1000 cubic meters per second.
- The turbine is named after its inventor Victor Kaplan, an Austrian engineer who developed the design in the early 20th century.

Pelton Wheel:

- A Pelton wheel is a type of impulse turbine that is suitable for high head and low flow rates.
- It uses a jet of water to impinge on a series of buckets on a rotating wheel to generate power.
- The buckets are designed to capture the energy of the water jet and convert it into rotational motion.
- The Pelton wheel operates with a high efficiency at high heads, but is not suitable for low head applications.

Francis Turbine:

- A Francis turbine is a type of reaction turbine that is suitable for medium head and medium flow rates.
- It uses a spiral casing to direct the water onto a series of stationary guide vanes, which then direct the water onto a series of rotating blades.
- The blades are curved to create a reaction force that generates power.
- The Francis turbine operates with a high efficiency over a range of flow rates and heads, but is not as efficient as the Kaplan turbine at low heads.

Conclusion:

- In summary, the Kaplan turbine is the most suitable turbine for low head and high flow rate applications.
- The Pelton wheel is suitable for high head and low flow rate applications, while the Francis turbine is suitable for medium head and medium flow rate applications.