# Difference Between Impulse and Reaction Turbine [With PDF]

Contents

## Introduction

In an Impulse turbine, all hydraulic energy is converted into kinetic energy by a nozzle. While In a reaction turbine, only some of the available energy is converted into kinetic energy. Before further detailed explanation let’s have some overview of Impulse and Reaction Turbine.

## Impulse Turbine

The impulse turbine changes the velocity of the water jet. The jet impinges on the turbine’s curved blade which changes the direction of the flow. The resulting change in momentum (impulse) causes an impact force on the turbine blades. Since the turbine is spinning, the force acts through a distance, and the diverted water flow is left with diminished energy.

Before hitting the turbine blades, the water pressure (potential energy) is converted to kinetic energy by a nozzle and focused on the turbine. No pressure change occurs at the turbine blades The turbine doesn’t require housing for operation. Newton’s second law describes the transfer of energy for an impulse turbine. Impulse turbines are most often used in very high head application. This turbine works at atmospheric pressure.

The following are the types of Impulse turbines:

## Reaction Turbine

Reaction turbines are acted on by water which changes pressure as it moves through the turbine and gives up its energy. They must be encased to maintain the water pressure (or suction), and they must be fully submerged in the water flow.

Newton’s third law describes the transfer of energy for the reaction turbine. Most water turbines use a reaction turbine. They are used in low and medium-head applications. This turbine works above atmospheric pressure. The following are the types of Reaction turbines:

## FAQ:

### What is Impulse Turbine?

The impulse turbine changes the velocity of the water jet. The jet impinges on the turbine’s curved blade which changes the direction of the flow. The resulting change in momentum (impulse) causes a force on the turbine blades.

### What is the Reaction Turbine?

Reaction turbines are acted on by water which changes the pressure as it moves through the turbine and gives up its energy. They must be encased to contain the water pressure or suction ,and they must be fully submerged in the water flow.
Newton’s third law describes the transfer of energy for the reaction turbine. Most water turbines uses a reaction turbine.

### What is the difference between the Impulse and Reaction Turbine?

In an Impulse turbine, all hydraulic energy is converted into kinetic energy by a nozzle whereas, in a Reaction turbine, only some amount of the available energy is converted into kinetic energy.