JTK Power, Wärtsilä and VTT Technical Research Centre of Finland have been working together to develop a special silencer designed for the testing conditions of Wärtsilä’s new Smart Technology Hub. JTK Power will supply a total of 21 silencers for the Smart Technology Hub, two of which will be special silencers.

They will be utilised in the test run exhaust gas ducting systems of engines designed for marine and power plant applications. JTK Power’s Design and Development Manager Jouni Hartikainen explains that special silencers are needed to produce reliable noise measurement results.

“This product is a special resistive silencer. In this case, it attenuates noise and also attenuates the reflection of sound waves back towards the source. This will ensure that the testing will provide reliable noise measurement results, and we can be confident that there will be no reflected sound waves.”

Acoustic design by VTT

The special silencers are the result of joint development work. Their acoustic design was carried out by Senior Scientist Jukka Tanttari from VTT. According to Tanttari, the silencers are unique in terms of structure and size, as the larger special silencer is 14 metres long and weighs 35,000 kilogrammes. The requirements for the silencers’ acoustic functions were quite exceptional, which is why they are one and a half times larger than normal.

“Engines produce noise at a low frequency, which gives the sound a long wave length. This requires the silencers to be large too. Due to the need to minimise noise reflections, the structure of the silencer is also exceptional, being conical and widening gradually,” Tanttari says.

JTK Power carried out a detailed structural design of the special silencers and is also their manufacturer. The first special silencer has already been completed and tested.

The silencers guarantee a quiet factory even in the middle of a residential area

Vibration and noise engineer Kari Saine from Wärtsilä says he is very happy with the cooperation with JTK Power and VTT. As the Smart Technology Hub under construction will be located in Vaskiluoto, Vaasa, just a hundred metres from residential buildings, the silencer will play a huge role in minimising noise emissions.

Wärtsilä, JTK Power and VTT have worked together in close cooperation for more than 20 years.

“JTK Power is an excellent partner, because they develop their own products as far as possible and have outstanding expertise in-house. The high quality JTK Power produces is also very important to us. There must be no noise impact, whether the engine is in the middle of the town or on a passenger ship.”

Saine explains that every person involved in the project has brought their special expertise to it, resulting in a final product that everyone is satisfied with.

“Wärtsilä has extensive experience of test conditions, VTT is an expert in modelling and JTK Power has years of experience in manufacturing silencers. Consequently, we have the best know-how available in this project.”

The special silencers were developed as part of Wärtsilä’s SOPEVA project, which is co-funded by Business Finland, a public agency for research funding and international promoter for Finnish industries.