Sound Transmission in Automotive Turbochargers

Experimental acoustic characterization of automotive twin-scroll turbine

“…This is an extension of previous works (Rämmal and Åbom 2009, Tiikoja et al 2011, Kabral et al 2013) concerning accurate measurements of turbo-charger acoustics, which only have covered two-ports (one inlet/outlet) configurations. By presenting and discussing the measurement methodology and test-rig design in detail it is shown how high quality data can be experimentally obtained under controlled laboratory conditions.…”

“…The experimental determination of turbine acoustic data from on-engine test rigs have proved to be challenging (Peat et al 2006). Therefore, building a dedicated acoustic turbo-charger test rig as is described in the present paper is a way to secure high quality data, which is nowadays essential in order to validate numerical models both reduced order models (Veloso 2012) and more advanced models (Sundström 2017). Also the first results of measurements on a twin-scroll turbine are presented and briefly discussed in the paper.…”

“…While a number of aerodynamic field studies are reported on the twin-scroll type turbine, and a few studies have considered single scroll turbine acoustics (Peat et al 2006, Tiikoja et al 2011, Veloso et al 2012, the acoustic properties of a twin-scroll turbine have, according to the knowledge of the authors, not been investigated. It is therefore of interest to extend the previous work on acoustic characterization of single scroll turbines to twin-scroll turbines.…”

“…In the present work, the unique test facility for acoustic testing of turbochargers at the KTH CCGEx laboratory, also used in the previous works on turbocharger acoustics (Rämmal and Åbom 2009, Tiikoja et al 2011, Kabral et al 2013, is further developed to enable the experimental investigation of twin-scroll turbines. The new test-rig is then used to experimentally determine acoustic performance data for an automotive twin-scroll turbine under controlled laboratory conditions.…”

Compact High-Pressure Intake Silencer with Multilayer Porous Material

“…In the case of turbocharged engines, particular problems arise [2]: on one hand, the influence on orifice noise of the waves generated by the sequence of opening and closing valves has been reduced dramatically. Indeed, both the turbo-compressor itself [3,4] and the charge air cooler [5] introduce significant damping for those low frequencies issues. On the other hand, new sources appear in the mid and high frequency range [6].…”