Multi stage diffuser silencers

There are a number of different ways to tackle industrial noise. For example, you could choose acoustic enclosures to prevent it from escaping a specific area. Or you can use silencers to reduce the decibels. They can work in different ways, including turning sound in to heat (absorbing) or reducing the pressure (diffusing). A diffuser silencer can be the best option in many cases.

How do diffusers work?

The basic idea here is that high pressure gas can enter the silencer and expand. This brings the pressure down and is far better than releasing it directly. It can reduce the noise because the lower pressure will be closer to the atmosphere.

What you will generally find with diffusers is a pipe that will funnel the gas into the centre of the silencer. There will usually be small holes in the pipe so the gas can expand and diffuse as it moves outward. As it does, the pressure will come down. It will then meet the shell of the diffuser silencer and can be expelled.

Some silencers have multiple stages here for the gas to diffuse. For example, there may be a secondary expansion step with that has a higher number of even smaller holes. What happens is the gas comes through the diffuser pipe, expands and loses pressure when it enters the silencer, then expands and loses even more pressure when it hits this secondary diffuser.

In some cases the diffusers can feature even more expansion steps. It all depends on the pressure drop you need to achieve. Sometimes you may even need an insert of filler material. Flow resistant stainless steel can be a good choice here. You can have it between the expansion steps.

There are also situations where you need one more stage of silencing here. If there is a lot of noise to tackle and you still need to reduce the pressure, the silencer may need an absorber above the diffuser section.


There are some fantastic benefits with a diffuser silencer. The most notable is you can often choose a small, light design. The advantage here is you typically don’t need to accommodate sound absorbing material. As a result, the silencers can be smaller and lighter. In turn that can make installation easier.

In addition, you can obtain a really good level of sound reduction. It is common to see this be as much as 50 dB(A) without sound absorbing material. It can be possible to achieve more than this with the right designs.

You can use this kind of silencers for a huge array of applications. For example, they are common for natural gas pipelines and power stations that need to vent hot steam. You can also see them at places like paper mills. If any operations have safety, gate, or control valves, they can be useful here too. You can even find them on boiler condensers.

Speak to us if you need a diffuser silencer

At Ventx we understand the benefits of silencers. They can make industrial operations much safer, especially when they generate a harmful level of noise. That is important for worker health and safety as well as the environment. Reducing the sounds can also be vital for performance, especially if you have any sensitive equipment.

So, ask us about designing silencers. We will use specialist software to analyse your operations and the noise level. The data will help us to decide what model would be best for you. It may be a diffuser silencer, an absorptive model, or one that combines both. Whatever the choice, we will deliver the best results.