Acoustic chamber for optimizing noise in cars equipped with Simcenter software
Linas-Montlhéry, France. Utac Ceram (UTAC) is located at Linas- Montlhéry, France, and offers services to all sectors involved in landbased movement. For example, Utac supports automotive manufacturers as they ensure noise levels from vehicles comply with regulations on noise pollution. To achieve this, Utac uses an acoustic chamber in which manufacturers can precisely measure and analyze the noise produced by their vehicles. The acoustic chamber is equipped with software from Siemens PLM Software.
Noise makes us sick – this is a scientifically proven fact. More and more governments are therefore tightening the regulations on maximum permissible noise levels. The limit for motor vehicles Europewide is currently 72 decibels (dB) and this is to be reduced to a maximum of 70 dB by 2020 and a maximum of 68 dB by 2024. The French company Utac Ceram supports automotive manufacturers in testing their vehicles for optimization opportunities and, ideally, in passing certification and homologation (approval) tests at the first time of asking. The company thus offers its customers, amongst other things, an ultramodern acoustic chamber at its LinasMontlhéry site in which noise generation and the causes of noise can be determined in the vehicle. Utac also supports manufacturers of hybrid and electric vehicle in the development of warning signals which indicate that the otherwise silent vehicle is approaching. The software utilized in the soundproof chamber comes from Siemens PLM Software.
Reproducible tests for accurate results
The unit is equipped with all-wheel drive rollers, a large number of microphones
and the LMS Test.Lab and LMS SCADAS software solutions. The acoustic chamber is therefore able to simulate all types of vehicles passing by and to augment this in the test process, thus supplying highly accurate test results. The Indoor
Pass-by Noise Tests allow the team to carry out repeatable tests in a controlled environment, irrespective of weather conditions. Vehicle speed and gear changes are automated which eliminates operator error. However, it is difficult to reproduce tire noise as this sounds different on a roller when compared to actual road conditions. This is where the Siemens solutions steps in. The LMS Test.Lab Pass-by Noise Testing software is part of the Simcenter portfolio and offers a tire noise calculation model which corrects tire noise data in accordance with procedures to ISO 362-3: 2016.
Acoustic warning signals
The acoustic chamber is not solely used for testing the reduction in pass-by noise. Utac supports manufacturers of hybrid and electric vehicles in equipping their vehicles with warning devices which produce a noise, also known as an Acoustic Vehicle Alerting System (AVAS). Utac uses LMS Test.Lab to define the minimum alarm level. According to Louis-Ferdinand Pardo, Acoustic Expert Leader and Department Manager, Electromagnetic Compatibility and Noise, Vibration and Harshness at Utac, there are many reasons to choose solutions from Siemens PLM Software. The software offers excellent data quality and processing capabilities for indoor pass-by noise tests. Using LMS testing solutions also ensures continuity and compatibility of tests performed indoors with tests executed outdoors. “We benefit from almost all the implemented functionalities of LMS
Test.Lab, and despite being advanced users, we still appreciate the easy-to-use worksheets and intuitive workflow approach,” concludes Yori.