Mechanical and Aerospace Engineering Colloquium Series
All lectures are held at 3:30 p.m. in the Engineering Building, Room B120, Busch Campus. Social period begins at 3:15 p.m.
November 11
Dr. Bill Robert
Factory Mutual Global
"An Overview of Strategic Fire Research at FM Global"
An overview of the fire research organization of FM Global will be given including a discussion of relevance to industrial property insurance, research objectives, resources, and current key projects. A particular commitment of the fire research effort is to reduce the need for large-scale fire testing through fire modeling. The current modeling efforts are divided into a fire modeling program and a suppression program. Some of the key aspects of these programs will be discussed including selection of the open source code Open FOAM as a computing platform. The fire modeling efforts include: experimental methods to identify flammability properties coupled with pyrolysis models, combustion, and heat transfer. Because heat transfer in large-scale fires is dominated by flame radiation, modeling of soot formation and oxidation has been identified as the critical research need. In the suppression program experimental efforts have been initiated to characterize the spray of commercial fire sprinklers, the transport of the spray through the gas phase, and water flow interactions with burning fuel surfaces. Use of intermediate-scale configurations to validate models and to provide critical program milestones will be discussed.
November 4
Honeybee Robotics Spacecraft Mechanisms Corporation
"Approach to “Living off the Land” on the Moon and Mars"
“Living off the land”, the way Luis and Clark did as they traversed America, has been NASA’s motto for quite some time now for the Lunar, and to some extend for the Martian exploration. The reason is the same: reduce the mass of required supplies and in turn make exploration affordable. For planetary exploration cutting down the cost is even of more importance; delivering just 1 pound to the surface of the Moon can cost upwards of $50,000. The difference between the ‘Luis and Clark’ and NASA approaches, however, is that Luis and Clark did not have to develop any new technologies. They took every day items. NASA, on the other hand, has to develop new technologies that will be able to work in the extreme conditions encountered on the Moon. These include extreme low temperatures down to 20 K (-420F), extreme hot temperatures in excess of 120 °C (250F), hard vacuum, communication delays, low gravity, and many others. This presentation will give an introduction to space exploration with a focus on human settlement on the Moon. The emphasis will be given to describing technologies that are being developed to make the permanent human presence on the surface of the Moon a reality. Some of these technologies include excavating and mining machines for building blast protection burms, launch pads, roads and mining regolith for In Situ Resource Utilization reactors, such as Oxygen extraction system.
October 28
Arizona State University
"Locomotion of Synthetic Nanomotors"
A nanomotor is a nanometer scale system capable of converting chemical energy into movement and can typically generate picoNewton forces. Eukaryotic cell locomotion and active cellular transport is largely driven by biological molecular motors. These protein nanomotors generate movement by converting the free chemical energy released by the hydrolysis of ATP to mechanical work. The controlled motion of synthetic nanoscale motors may represent a major step towards the development of practical nanomachines, artificial cells, and autonomous microsystems. At ASU, we are investigating locomotion of bimetallic synthetic nanomotors that, analogous to their biological counterparts, harvest chemical energy from their local environment and convert it to useful work. Bimetallic nanorods can autonomously propel themselves at a hundred body lengths per second through aqueous solutions by using hydrogen peroxide as a fuel. Magnetic fields and electrochemically induced chemical species are used to control the motion of Pt-Ni-Au nanorods. We use the magnetic properties of nickel-loaded nanomotors to control their motion through micron-scale structures as well as the loading, transport, and release of spherical cargo that have volumes two orders of magnitude larger than the nanomotors itself. Nanomotor locomotion forces are determined by measuring their velocity while towing spherical cargo that have Stokes drag eight times the nanomotors themselves. Several physical arguments have been proposed to describe the physics underlying chemically-powered locomotion, but there is no detailed theory on the propulsion mechanism. We are simulating the physics of rod-shaped nanoparticles with asymmetric surface fluxes. Our models show that locomotion is driven by electric body forces in the fluid that arise due to finite space charge and internally generated electric fields surrounding the rod. The electric fields and charge density are generated by dipolar cation fluxes, such as those generated by heterogeneous electrochemical reactions with broken symmetry. The scaling analysis and detailed simulations predict that the nanomotor velocity depends on the reaction flux, nanorod electrical surface potential, solvent viscosity, and rod geometry.
October 21
Purdue University
"ULTRAFAST ENERGY TRANSFER IN NANOSCALE ENERGY CONVERSION MATERIALS"
The key in increasing commercial applications of energy conversion materials, such as thermoelectric and photovoltaic materials is to increase their energy conversion efficiencies and reduce cost/watt of energy conversion. Recently, there are significant progresses in energy conversion research; many are resulted from the discoveries in nanoscience, nanotechnology, and many unique properties of nanomaterials. In our laboratory, we carry out fundamental studies of energy transfer and conversion. At the microscopic level, interactions among basic energy carriers (photons, electrons, and phonons), which often occur at a time scale of picosecond (10^-12 sec) or sub-picosecond, are directly related to the energy conversion efficiency. For example, in photovoltaic material, it is necessary to decrease the electron-phonon interaction rate, therefore increasing the current output; whereas in thermoelectric materials, many researches are focused on increasing phonon scattering and reducing the lattice thermal conductivity. We developed a laser-based coherent phonon spectroscopy technique to investigate interactions among basic energy carriers, in particular, phonon dynamics at the ultrafast time scale. This technique has femtosecond (10^-15 sec) time resolution, capable of measuring atomic vibrations which typically have oscillation periods of the order of hundreds of femtoseconds. We applied this technique to investigate superlattice, quantum dot, and other types of energy conversion materials in which energy transfer rate and/or heat generation need to be enhanced or suppressed. Interactions among energy carriers and between energy carriers and physical boundaries, interfaces, and impurities are studied in details. Results of these studies will help the design of novel nanoscale energy conversion materials.
October 14
Astronaut Lee Morin, M.D., Ph.D.
NASA Houston
“Rocks to Robots: Concepts for Lunar Resource Utilization”
An approach to bootstrapping of lunar resources will be discussed. This concept combines telepresence and dexterous robotics with lunar regolith material processing to perform in-situ resource utilization (ISRU). By targeting the initial ISRU at increasing the ISRU capability itself, exponential growth in lunar industrial capability may be possible starting with modest, affordable missions not requiring heavy lift.
October 7
New Jersey Institute of Technology (NJIT)
“Particle Engineering for Property Enhancements”
This talk will provide an overview of research work of Prof. Davé on creation of advanced particulate materials through engineering of particles, with applications to pharmaceutical, bio, energetic, and specialty chemical materials. In most such cases, the emphasis is on a more effective utilization of the unique properties of nano and sub-micron particles through structuring/engineering of the particulates. Engineered particles can have improved characteristics such as dispersability, flowability, wettability, sinterability, size uniformity, proper morphology, reduced tendency for segregation, as well as having tailored electrical, electro-magnetic, optical, thermal or other properties; and hence have wide applicability to various industrial problems. The presentation will present recent work on the use of dry coating for particle property modification, specifically flow improvement and subsequent processing. It will also include the topic of characterization for flow and other important properties and our research related to bridging the gap between particle scale properties to bulk scale properties. Talk will also discuss particle engineering involving formation and stabilization of particles, film coating, nano-composite formation and mixing at nano-scale. The talk will also include an overview of Prof. Davé’s involvement in the NSF-ERC (National Science Foundation Engineering Research Center on Structured Organic Particulate Systems- ERC-SOPS), emphasizing the need for interdisciplinary team based research that requires expertise from engineering and sciences. Prof. Davé is the NJIT Site Leader, a Thrust Leader and a Test-bed leader of the ERC-SOPS.
September 30
Dr. Suhada Jayasuriya, Program Director
Control Systems, NSF/CMMI
"Funding Opportunities at the NSF and a Perspective on Cooperative Control Research"
The presentation includes two separate topics: 1. a brief overview of NSF programs and funding opportunities in the Control Systems Program within CMMI division in the ENG directorate, and 2. some recent results and new directions in cooperative control research. Considered is a class of problems in coordinating multi-agent systems that include the so called radar deception problem, rigid formation keeping and reconfiguration. Cooperative deployment of agents to accomplish the associated tasks is dominated by task coupling, partial information, and uncertainty. Being able to move a team of networked agents from a reference configuration (location and shape) A to a goal configuration B is fundamental, and provides the basis for, their effective deployment. A geometric formulation of the associated constraints provides a unifying framework for these three problems. A real time motion planning algorithm that generates feasible reference trajectories for these problems is proposed. A unique feature of the approach is that it explicitly considers actuator and other operating constraints and derives the constrained dynamics of the multi-agent system in a way that these constraints become transparent. This approach to deriving constrained dynamics eliminates the need for nonlinear programming methods to account for system constraints thus making it very attractive for real time control. In addition the explicit consideration of actuator and operating limits and nonholonomic constraints in the synthesis of reference trajectories addresses the important issue of dynamic feasibility of such trajectories.
September 23
Iowa State University
"3D X-Ray Flow Visualization of Fluidized Beds"
Fluidized Beds are found in many process industries including combustion, pyrolysis, and gasification of solid fuels such as coal or biomass. They are also commonly used in the drying and coating of pharmaceuticals. Understanding the hydrodynamics of fluidized beds is important for better process performance; however, quantifying the hydrodynamics is extremely challenging because the systems are opaque and highly dynamic. X-ray imaging is on noninvasive method that can be used to characterize and quantify the fluidized bed hydrodynamics. This seminar will provide an overview of a unique X-ray flow visualization facility that can complete 3D X-ray computed tomography (CT) imaging of a multiphase flow to measure the local time-averaged phase fractions anywhere within the imaging region. Several different fluidized bed conditions have been imaged and selected results will be presented. The use of X-ray Particle Tracking Velocimetry (XPTV) to track individually injected particles in a fluidized bed will also be demonstrated.
Past Colloquium Series
The Support of the DuPont Company, The Procter and Gamble Fund, Exxon Education Foundation, Ingersoll-Rand Company, The Torrington Company and our Alumni made this Colloquium Series possible.