title: Adaptive muffler based on controlled flow valves.
abstract: An adaptive muffler with a flexible internal structure is considered. Flexibility is achieved using controlled flow valves. The proposed adaptive muffler is able to adapt to changes in engine operating conditions. It consists of a Helmholtz resonator, expansion chamber, and quarter wavelength resonator. Different combinations of the control valves' states at different operating conditions define the main working principle. To control the valve's position, an active noise control approach was used. With the proposed muffler, the transmission loss can be increased by more than 10 dB in the selected frequency range.
authors.affiliation: University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia peter.steblaj@fs.uni-lj.si, mirko.cudina@fs.uni-lj.si, primoz.lipar@fs.uni-lj.si, prezelj.jurij@gmail.com.
authors.forename: Peter
authors.initials: P
authors.lastname: Šteblaj
authors.affiliation: University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia peter.steblaj@fs.uni-lj.si, mirko.cudina@fs.uni-lj.si, primoz.lipar@fs.uni-lj.si, prezelj.jurij@gmail.com.
authors.forename: Mirko
authors.initials: M
authors.lastname: Čudina
authors.affiliation: University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia peter.steblaj@fs.uni-lj.si, mirko.cudina@fs.uni-lj.si, primoz.lipar@fs.uni-lj.si, prezelj.jurij@gmail.com.
authors.forename: Primož
authors.initials: P
authors.lastname: Lipar
authors.affiliation: University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana, Slovenia peter.steblaj@fs.uni-lj.si, mirko.cudina@fs.uni-lj.si, primoz.lipar@fs.uni-lj.si, prezelj.jurij@gmail.com.
authors.forename: Jurij
authors.initials: J
authors.lastname: Prezelj