# What is a convergent divergent duct?

## What is a convergent divergent duct?

A duct that has a decreasing cross section in the direction of fluid flow is convergent, until a minimum area is reached. Thereafter, the cross section increases, or becomes divergent.

## What happens convergent duct?

A duct whose cross-sectional area decreases in the direction of fluid flow. They work by spinning an impeller that throws the air outward through a convergent duct with diffuser veins to direct the compressed gas on to the combustion chamber.

What is a divergent duct?

A duct whose cross-sectional area increases in the direction of fluid flow. At subsonic speeds, the flow velocity decreases and the pressure rises. An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc.

How does a convergent-divergent nozzle work?

This nozzle configuration is called a convergent-divergent, or CD, nozzle. In a CD nozzle, the hot exhaust leaves the combustion chamber and converges down to the minimum area, or throat, of the nozzle. The exit velocity, pressure, and mass flow through the nozzle determines the amount of thrust produced by the nozzle.

### Why is a diverging nozzle converging?

A converging diverging nozzle is generally intended to produce supersonic flow near the exit plane. If the back pressure is set at (vi), the flow will be isentropic throughout the nozzle, and supersonic at nozzle exit.

### How does a convergent divergent nozzle work?

What will happen in divergence duct for supersonic airflow?

As Supersonic air flow enters into a Divergent Duct its velocity will increase & its pressure will decrease. D. A Divergent Duct acts as a Nozzle for Super-Sonic Airflow 1. The reason for supersonic airflow’s velocity to increase & its pressure to decrease as it flows into a convergent duct is as follows: a.

Why nozzles are made convergent and divergent?

Convergent-divergent type of nozzles are mostly used for supersonic flows because it is impossible to create supersonic flows (mach number more than one) in convergent type of nozzle and therefore it restricts us to a limited amount of mass flow through a particular nozzle.

#### What is divergent nozzle?

[də′vər·jənt ′näz·əl] (design engineering) A nozzle whose cross section becomes larger in the direction of flow.

#### What is the difference between convergent and divergent ducts?

convergent-divergent duct. Relationship of pressure, temperature, and velocity in a convergent-divergent duct. A duct that has a decreasing cross section in the direction of fluid flow is convergent, until a minimum area is reached. Thereafter, the cross section increases, or becomes divergent.

What is a convergent divergent nozzle?

This nozzle configuration is called a convergent-divergent, or CD, nozzle. In a CD nozzle, the hot exhaust leaves the combustion chamber and converges down to the minimum area, or throat, of the nozzle. The throat size is chosen to choke the flow and set the mass flow rate through the system.

What happens when the cross section of a fluid becomes divergent?

Thereafter, the cross section increases and becomes divergent. The velocity of fluid will increase when the as the fluid enters the converging section considering the mass flow rate to be constant.

## What happens to the pressure head if the duct is inclined?

If the duct was inclined upwards the pressure head will increase at the upstream due to difference in height , but the total head loss will stay constant . The flow will continue until the pressure head at upstream equals the elevation head at downstream thus velocity head will be zero and the fluid comes to rest.