Bellmouth reducers have smaller openings at the ends of duct systems. Bell mouth reducers look like a bell shape. Fabric expansion joints are sometimes used in a duct system. We also provide ducting expansion joints. Bellmouth reducers help return air or extract air in building ventilation systems.
The open area of the Bellmouth reducer is usually twice that of its duct. The air entering the bellmouth reducer is therefore low. This reduces noise, turbulence, and pressure drop. The Bellmouth fitting shape allows maximum airflow into the duct while minimizing loss.
Bellmouth reducers are used to lower the pressure drop at an intake into a conduit from an open space. Bellmouth reducers can also be discharged from a chimney into open spaces. This is also known as shock loss, or more commonly, fitting pressure loss.
The velocity pressure is equal to the fitting pressure loss for an intake ducted from an area. It is therefore equal to the square root of the velocity. You can reduce the pressure drop by increasing the area of the intake. To reduce shock losses at entry, a bellmouth reducer is also used.
A bellmouth reducers duct inlet duct is a type of convergent air duct that directs air into the inlet of an engine as the engine receives more air, the area of the convergent conduit shrinks.
The bellmouth reducer inlet conduit is extremely efficient and useful when there is insufficient pressure to force air into the engine. These ducts can be found in engine test cells or on engines that are installed in helicopters.
How to Choose a Bell Mouth Reducer
The velocity of the air used to reduce the bellmouth is important. Know the dimensions and well of the duct. And the CFM is being handled by the duct section. For smooth air entry/exit, bell mouth reducers must be tapered at 45 degrees.
Learn more about Q=Av. Finally, you will need to calculate the maximum size of the bellmouth reducer using all the information.
How do you find the maximum size of Bellmouth Reducers?
The maximum size is determined by the inlet velocity you desire. It’s not about the size. It’s also about geometry.
You can get the air moving at speeds up to 4-5m/sec or as low as 0.01m/sec if the air is going to “drift” in and out. There are many end areas that you can choose from depending on your specific requirements and concerns.
You should be aware that the velocity in the middle of the area will be much greater than the one at the edge.
Q=Av is the area of the bellmouth reducer’s entrance/exit. The duct is the other end.
Because the pressure drop in the bellmouth reducer is higher than the exhaust air, the entry air is typically slower. Although the inlets are the same size as the bellmouth reducer, they can cause noise and losses as the air enters the duct.