Home | | Power Plant Engineering | Draught and Wright the types of Draught

Chapter: Mechanical and Electrical - Power Plant Engineering - Coal Based Thermal Power Plants

| Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail |

Draught and Wright the types of Draught

Draught is defined as the difference between absolute gas pressure at any point in a gas flow passage and the ambient (same elevation) atmospheric pressure.


Draught and Wright the types of Draught

 

Draught:

 

 

Draught is defined as the difference between absolute gas pressure at any point in a gas flow passage and the ambient (same elevation) atmospheric pressure. Draught is plus if Patm < Pgas and it is minus Patm > Pgas. Draught is achieved by small pressure difference which causes the flow of air or gas to take place. It is measured in milimetre (mm) or water.

 

The purpose of draught is as follows:

 

i)                  To supply required amount of air to the furnace for the combustion of fuel

 

The amount of fuel that can be burnt per square root of grate area depends upon the quantity of air circulated through fuel bed.

 

ii)                 To remove the gaseous products of combustion.

 

 

Classification of DRAUGHT:




If only chimney is used to produce the draught, it is called natural draught.

 

Artificial Draught

 

If the draught is produced by steam jet or fan it is known as artificial draught

 

Steam jet Draught:

 

It employs steam to produce the draught

 

Mechanical draught

 

It employs fan or blowers to produce the draught.

 

Induced draught

 

The flue is drawn (sucked) through the system by a fan or steam jet

 

Forced draught

 

The air is forced into system by a blower or steam jet.

 

Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail


Copyright © 2018-2021 BrainKart.com; All Rights Reserved. (BS) Developed by Therithal info, Chennai.