What is the Difference Between Impulse Turbine and Reaction Turbine?

The main difference between an impulse turbine and a reaction turbine lies in how they convert the energy of a fluid, such as water or steam, into rotational mechanical energy. Here are the key differences between the two types of turbines:

Impulse Turbine:

Uses only the kinetic energy of the fluid to spin the turbine.
The fluid's pressure is converted into kinetic energy in a nozzle, and then the velocity of the fluid jet is used to rotate the turbine.
There is a pressure drop across the fixed blades only.
The most common type of impulse turbine is the Pelton turbine.

Reaction Turbine:

Uses both the pressure and kinetic energy of the fluid to spin the turbine.
The fluid's pressure drops across both the fixed and the moving blades.
More efficient than impulse turbines due to the use of both pressure and kinetic energy.
Reaction turbines include Francis turbines and Kaplan turbines, which are popular types of water turbines.

In summary, impulse turbines rely on the kinetic energy of the fluid, while reaction turbines utilize both the pressure and kinetic energy of the fluid to generate rotational mechanical energy. Reaction turbines are generally more efficient than impulse turbines due to their ability to harness both forms of energy.

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What is the Difference Between Impulse Turbine and Reaction Turbine?

Comparative Table: Impulse Turbine vs Reaction Turbine

The main difference between impulse and reaction turbines lies in how they convert the potential energy of a fluid into rotational mechanical energy. Here is a table summarizing the key differences between impulse and reaction turbines:

Basis of Difference	Impulse Turbine	Reaction Turbine
Definition	An impulse turbine uses the impulse of a fluid to rotate the turbine. The fluid's kinetic energy is converted into mechanical energy as it strikes the turbine blades.	A reaction turbine uses both the pressure and kinetic energy of the fluid to rotate the turbine. The fluid first flows through stationary blades (stator) to increase its velocity, then enters a set of moving blades (rotor) to extract its kinetic energy.
Principle of Operation	Operates based on the impulse principle.	Operates based on the reaction principle.
Fluid Flow	The fluid flow is usually high velocity and low mass flow rate.	The fluid flow is usually low velocity and high mass flow rate.
Application	Typically used for high-head applications, such as water turbines in hydroelectric power plants.	Typically used for low-head applications, such as gas turbines, water turbines, and steam turbines.
Efficiency Factor	Maximum efficiency depends on the \eta _{max}=cos^2{\alpha _{1}} factor for steam impulse turbines.	Efficiency is a function of various factors, including the velocity and pressure of the fluid.
Examples	Francis turbine and Kaplan turbine are popular reaction-type water turbines.	Pelton wheel is a common impulse turbine used in hydroelectric power plants.

Understanding these differences is crucial for selecting the right type of turbine for a given application.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.