Aerospace Engineering Seminar Series: "Rotorcraft Noise: Past, Present and Future” - Bhaskar Mukherjee
Thursday, January 29, 2026;
3:00pm-4:00pm
028 ECoRE
Speaker: Bhaskar Mukherjee from The Pennsylvania State University
Abstract: Rotor noise remains a major barrier to commercializing helicopters and emerging electric multirotor aircraft, often prompting curfews and flight caps. Accurate noise prediction has strong commercial value: it guides design tradeoffs and helps operators and airports manage community exposure. High-fidelity CFD is common for steady cases (e.g., hover), but real operations are unsteady; matching what communities hear requires time-accurate simulations over hundreds of revolutions—too expensive for CFD in practice. Mid-fidelity methods offer a better accuracy-to-cost balance, making maneuver noise prediction practical. As these models become faster and more accurate with growing computational power, new applications emerge beyond evaluating community noise impact. In autonomous operations, acoustics can complement vision and other sensors, adding cues that improve awareness and safety in shared airspace.
Speaker Bio: Bhaskar Mukherjee earned his PhD in Aerospace Engineering at Penn State, specializing in rotorcraft aeroacoustics, aerodynamics, and flight simulation. His dissertation developed mid-fidelity noise prediction tools for emerging electric vertical takeoff and landing (eVTOL) aircraft and helicopters. He received the Airport Cooperative Research Program (ACRP) Graduate Research Award for applying these methods to assess community noise around New York City heliports, considering both current helicopter operations and the potential introduction of eVTOL vehicles. He continues this research at Penn State, expanding noise prediction toward new applications in aircraft safety and autonomy.
Hosted by: Jessica Chhan, jmc7050@psu.edu
Physics of nanoscale spectral imaging beyond diffraction limit
Wednesday, January 28, 2026;
121 Earth & Engineering Science Building
335PM-425PM
Speaker: Slava Rotkin from ESM
Abstract: Recent success in synthesis of new two-dimensional materials (2DM) beyond graphene (including TMDCs, heteronanotubes, hBN family, MXenes and atomic polar metals), was followed by a large number of works exploring their properties and seeking for novel applications in quantum technologies, biosensing, energy and computing. Atomically thin 2DMs have an ultimate surface-to-volume ratio. While it helps biosensing, electronics and other applications, surface non-uniformities may drastically increase variability of materials properties. Such non-uniformities are known to be a critical limiting factor for other types of nanomaterials as well. Modulation of optical properties at the nanometer scale due to atomic impurities or adsorbates or defects, wrinkles or ruptures, lattice mismatch, doping and work function variation is important to be able to control. However, even before developing synthetic approach to mitigate the problem, appropriate characterization tools are needed to detect such a modulation.
In this talk, several methods for nanoscale (sub-diffractional) optical characterization will be presented. Correlated multiplexed (multidimensional) optical imaging technique will be introduced using a few examples including: a vertical heterostructure comprised of monolayer graphene and single layer flakes of MoS2,[1] heteronanotubes with carbon core and hBN/MoS2 shell,[2] glass nanoindentations[3,9] and heterostructures of graphene/Ag/SiC atomic layers[4,10]. The correlation of several information channels (including microRaman[5,6]) allows one to obtain information on, e.g., local Fermi level and strain tensor components[1] or distribution of chemical bonds in a glassy material[3].
It will be shown that similar results could be obtained using scattering Scanning Near-field Optical Microscopy (sSNOM), the technique which produces multidimensional information in a single run. sSNOM will be shown to map polaritonic wavefunction and detect polaritonic confinement in heterostructures of atomic-thin metals[10]. As the time allows, a quantum theory of sSNOM imaging will be discussed [7,8].
Literature:
1. ACS Nano 2022, 16, 2598.
2. ACS Nano 2021, 15, 5600.
3. Acta Materialia 2021, 208, 116694.
4. Science Advances 2025, 11, eadw1800.
5. Nature Comm 2015, 6, 8429.
6. J Mat Chem B 2017, 5, 6536.
7. ACS Nano 2015, 20, 360.
8. S.V. Rotkin, Materials Science & Technology 2022 (October 9-13, Pittsburgh, PA).
9. Ceramics International 2024, 50 Part A, 32457.
10. X. Li, et.al, (submitted).
Bio:
Slava V. Rotkin is Frontier Professor of Engineering Science & Mechanics at Penn State University. He received MSc in Optoelectronics from Electrotechnical University and Ph.D. in Physics & Mathematics at Ioffe Institute (St. Petersburg, Russia). Rotkin is an editor of 3 books and author of 190 papers and proceedings. Most recently, his work is focused on near-field optics and plasmonics, nano-biophysics, and 2D quantum materials. Rotkin mentored 30+ graduate students, 10+ postdoctoral fellows, 60+ undergraduates and a dozen of high-school students. Rotkin is recipient of several scientific awards, including Fellow of the Electrochemical Society, The Fulbright-Nehru Academic and Professional Excellence Award, The Japan Society for the Promotion of Science Fellowship, the Japan Gateway: Kyoto University Distinguished Professor, Hillman Award, Class of '68 Fellowship, Libsch Early Career Research Award, Feigl Junior Faculty Chair, and Beckman Fellowship
Hosted by: Lana Fulton, lub18@psu.edu
