Experimental investigation of transmission loss in an automotive turbocharger compressor under ideal and real engine operating conditions

Abstract

Acoustic transmission losses are expected to occur over the turbocharger compressor, especially along its rotating wheel section. Experiments on the acoustic characteristics of automotive turbocharger compressors were performed to investigate this acoustic transmission loss behavior. Two different rotor sizes were acoustically investigated considering approximately the same performance characteristics of the compressors. The investigated variants passed through two phases of measurements: The first phase was performed under ideal operating conditions involving a steady non-pulsating flow on an acoustic component test rig for turbochargers. Whereas the second phase was conducted under real engine operating conditions including pulsating flow of a modern 6-cylinder gasoline engine on an engine test rig. Comparisons between the two measurement phases show a considerable agreement between the two test rig setups for different operating conditions.

Experimental acoustic characterization of automotive twin-scroll turbine

“…In this laboratory, the turbochargers are isolated from the IC engine and measured separately under controlled laboratory conditions on the unique test-rig for turbocharger acoustics. The results obtained from this laboratory, under controlled realistic operating conditions, are in good agreement with results obtained from on-engine measurements, and this is without any additional compensation (El Nemr et al 2017). …”

“…is formulated for all microphones, and the Euclidian norm of the vector is then minimized (Fujimori et al 1984), i.e. the least square problem is solved.…”