New underground railway cars in Hamburg with sound-optimised air
Underground railway car DT5 of the
Hamburg Aerial Railway Company Manufacturer:
Alstom LHB / Bombardier
Air conditioning device for the passenger room
DT5 (source of picture: Liebherr)
For the new underground railway cars of type DT5 (two-car trainset #5) of the Hamburg Aerial Railway Company, the air conditioning devices are being supplied by Firma Liebherr-Transportation Systems GmbH & Co. KG., Korneuburg.
The sound-optimised air conditioning devices were developed by Liebherr in close collaboration with IBS.
Test set-up for acoustical optimisation
Due to the successful collaboration of Liebherr and IBS, the strict requirements concerning the sound emission of the air conditioning devices could be met.
Parallel to the manufacturing process of the prototypes on Liebherr premises, on the components that had been assembled already sound measurements were conducted in order to determine the sound power level shares of individual sources (sound power level balance). Based on the results, optimisation measures were suggested that were being measured again after assembly. If necessary, the measurement / assembly loop was repeated until the requirements were met.