Energy losses in the drivetrain are a steady topic within the automotive industry, be it to lower emissions and fulfill demands by legislation or to stay longer on the track with a single filling of the fuel tank as in motor sport applications. All of these reasons fuel the motivation to reduce these parasitic losses. In this paper, the major sources of the energy losses in a gearbox are discussed. After the discussion of the sources, the losses in a longitudinally installed manual gearbox are investigated by using both experimental measurements as well as simulation. For the simulation, convenient empirical formulas from literature are used to describe the individual loss processes and combined together to describe the friction power losses of the entire gearbox. The comparison between simulation and the extensive experimental data show good agreement.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.