Weekly Seminar: Fall 2013
Speaker: Dr. Luc Mongeau (McGill University)
Title: "Applications of the Lattice Boltzmann Method for the Simulation of Flow and Sound from Lobed Mixers Jets"
Date: Friday, November 8, 2013
Time: 11:00 a.m.
Location: Gilman 50 (Marjorie M. Fisher Hall)
The growing stringency of community noise regulations for commercial turbo-fan engine requires the development of effective jet noise suppression configurations. Small engines for regional jets have relatively low bypass ratios because of size limitations. The large number of geometrical design parameters for lobed mixers makes trial and error experimental studies prohibitively expensive. A robust computational tool was used to investigate the effects of the lobed mixer design on the sound radiated by the jet. The near field sound and flow were simulated using a flow solver based on the Lattice Boltzmann Method (LBM). The far field radiated sound was predicted using the Ffwocs William-Hawkings (FWH) surface integral method. One baseline confluent nozzle and several nozzles with varying scalloping and lobe penetration depths were investigated. Low Mach number flow was assumed, with operating conditions selected to best approach conditions for actual engines. The effects of an outer mean flow to simulate forward flight were not included. The results suggested that scalloping doesn't always bring benefit to noise reduction, and that there exists an optimal value for scalloping depth. Results were in qualitative agreement with available experimental results.
Dr. Mongeau obtained his B.S. and M.S. degrees in Mechanical Engineering from Ecole Polytechnique, Montreal, in 1984 and 1986, respectively. He obtained his Ph.D. from the Pennsylvania State University in 1991. After nearly two years as postdoctoral member of technical staff at AT&T Bell Laboratories, Dr. Mongeau was first Assistant, then Associate, and eventually Full Professor in the School of Mechanical Engineering at Purdue University. Dr. Mongeau returned to Canada in 2006, where he is presently Professor of Mechanical Engineering at McGill University, in Montreal. He holds a Tier 1 Canada Research Chair position in flow-induced sound and vibration. He is presently on sabbatical leave at the John Hopkins University where he helps initiate a new research project on cardiovascular acoustics. His research program includes axes in biomechanics, aeroacoustics, and thermoacoustics. He presently supervise two postdoctoral research fellows, seven doctoral students, and one master’s student. He has served three years as Faculty of Engineering Associate Dean of Academic Affairs and Department of Mechanical Engineering Director of Graduate Admissions and Fellowships. He was a member of the ICAO independent expert panel on aircraft noise emissions in 2011-2012, and Technical Chair of the International Congress of Acoustics held in Montreal from June 2 to 7, 2013. He has authored or co-authored over 90 archival publications in 30 different peer reviewed journals. He is a member of ASME, a senior member of AIAA, a fellow of the ASA, and a senior member of the SAE.