MAE Seminar Schedule for Academic Year 2007-08
Unless otherwise noted, MAE seminars are held in
1065 Kemper Hall from 2:10 to 3:00 pm.
(Refreshments at 2:00 pm.)
| Thursday, October 11, 2007 | “Hi-Tech” Solutions to Quality Control Problems in Buildings |
| Thursday, November 8, 2007 | Cardiac Output, Pressure Gradients and Allometric Scaling of Metabolic Rates |
| Thursday, December 13, 2007
|
Recent improvements to Meshfree solutions of partial differential equations |
| Thursday, January 10, 2008 | Ion Mobility/Mass Spectrometery Of Aerosols: A New Approach To Organic Speciation |
Thursday, February 14, 2008 Time change to 4:10-5pm 1062 Bainer Hall |
Smart Physical Rehabilitation Devices and Their Controls |
| Special Seminar - Wednesday, March 12, 2:10pm - 1003 Kemper | Micro and Miniature Technologies of Advanced Energy and Thermal Systems (Fuel Cells and Heat Pipes) |
Thursday, March 13, 2008 Time change to 4:10-5pm 1062 Bainer Hall |
Advanced Flight Technology Concepts at Boeing Phantom Works |
Thursday, April 10, 2008 Time change to 4:10-5pm 1062 Bainer Hall |
Brain-Computer Interfaces
(Bcis) for Communication and Control |
Thursday, May 8, 2008 Time change to 4:10-5pm 1062 Bainer Hall |
Aerodynamic, Aeroacoustic and Aeroelastic Investigations of helicopter Blade-Vortex Interaction |
Thursday, October 11, 2007
“Hi-Tech” Solutions to Quality Control Problems in Buildings
Dr. Mark Modera
Vice President, Strategic Operations
Carrier Aeroseal, LLC
Indianapolis , IN
As compared to the automotive, aerospace and IT industries, a large fraction of the manufacturing process for single-family homes does not occur in a factory. One of the challenges this creates is a need for in-situ quality-control tools. This presentation briefly addresses three “Hi-Tech” solutions to air-tightness quality-control issues in buildings. Two solutions involve techniques for measuring the air-tightness of the exterior shell of a structure. The third solution involves continuously measuring and sealing leakage in an air distribution system without having to access the exterior of that distribution system. All three solutions stem from applying fluid mechanics and signal processing techniques to air leakage problems. One shell-leakage measurement technique involves changing the building volume in a sinusoidal manner, and the second leakage-measurement technique is based upon measuring the temporal pressure decay following a sudden increase in building pressure. The technique for sealing leaks in air distribution systems involves appropriate application of particle dynamics to get sealant particles to remain suspended during transport through the system, but then have those particles leave the air stream to deposit on distribution-system walls at any leaks.
Thursday, November 8, 2007
Cardiac Output, Pressure Gradients and Allometric
Scaling of Metabolic Rates
Dr. Page Painter
Office of Environmental Health Hazard Assessment
California Environmental Protection Agency
Sacramento, CA
Background
The field of allometry studies the relationship between body size and structural or functional parameters. A well-known example is the relationship between mammalian body size and the metabolic rate in a reproducible physiological state, R = a*M^b , where M is the body mass. In this power function, the constant b is the slope of the logarithm of the metabolic rate plotted as a function of the logarithm of body mass. When mammals are at rest, the constant b is approximately 0.70 and when they are in the state of maximum sustainable exercise, it is approximately 0.87.
Methods and Results
The pulmonary network of veins imposes resistance to blood flow (impedance) that places a limit on the rate at which blood can be pumped through the lungs before pulmonary edema occurs. The maximum pressure gradient that does not produce edema determines the maximum rate that blood can flow through the pulmonary veins without compromising the diffusing capacity of oxygen. We show that modeling the pulmonary venous tree as a fractal-like vascular network leads to a scaling equation for maximum cardiac output that predicts MMR as a function of M as well as the conventional power function does and that least-squares regression estimates of the equation's slope-determining parameter correspond closely to the value of the parameter calculated directly from Murray's law.
Conclusion
The assumption that cardiac output at the MMR is limited by pulmonary capillary pressures that produce edema leads to a model that is in agreement with experimental measurements of MMR scaling, and the rate of blood flow in pulmonary veins may be rate-limiting for the pathway of oxygen.
Thursday, December 13, 2007
Recent improvements to Meshfree solutions of partial differential equations
Dr. Edward Kansa
Adjunct Professor
Mechanical & Aeronautical Engineering
UC Davis
Abstract
The most popular meshfree radial basis function is the generalized multiquadrics (MQ), f j ( | | x-x j | | ) = [1 + { ( x - x j )/c j } 2 ] b , where b ³ -1/2, c j is the shape parameter, and x and x j Î Â d . f j depends only upon the radial distance between pairs of points in any dimensional space, Â , and is a non-orthonomalized wavelet with translational, dilatational, and rotational invariance. The spatial partial derivatives are obtained by analytically differentiating f j ; hence it is used in the solution of all forms of partial differential equations (PDEs), without the need to construct a mesh, especially over irregular, complex domains. f j also possesses exponential convergence of O( l m ) where 0 < l < 1 and m = c j /h, where h is the maximal point separation distance, h = | | x-x j | | ). It is this exponential convergence rate that has interested many persons worldwide. Finite elements converge at the rate O(h p ), where p is the polynomial order.
One can increase m by refining the discretization similar to finite difference or element methods, or increase c j . However, increasing m increase ill-conditioning that is treated with preconditioners and domain decomposition. A recent paper shows a quad-tree or oct-tree adaptive refinement scheme is computationally more efficient because the PDE solution is only refined near steep gradient regions, Another paper demonstrated that by choosing large c j near steep gradients, very accurate solutions can be obtained with a coarse discretization. Increasing c j is vastly more efficient. One can employ an improved truncates singular value decomposition method that casts an ill-condition system of equations into a well-condition one, or one can use extended precision arithmetic. With extended precision arithmetic, m is pushed to very large values, yet the CPU time is very modest since a very coarse discretization is required to obtain the same accuracy as a finely meshed finite element solution. Numerical results will be provided to demonstrate the efficiency of the meshless MQ method. The fast solvers for meshless MQ basis functions is still under development, and will most likely be a combination of the above-mentioned techniques.
Thursday, January 10, 2008
Denis J. Phares
University of
Southern California
Department of Aerospace and Mechanical Engineering
Los Angeles, California
Ion Mobility/Mass
Spectrometery Of Aerosols: A New Approach To Organic Speciation
Understanding
how small particles in the atmosphere affect health and the environment
requires knowledge of their chemical composition. Issues associated with
bulk aerosol analysis, such as low temporal resolution, size biases, and
chemical transformation after sampling, has led to the development of aerosol
mass spectrometers that can determine the chemical composition of ambient
aerosols in real-time. Some of these instruments have provided quantitative
data concerning the content of various salts and metals present in the aerosol.
However, identification of organic compounds is not yet possible, because
of the difficulty in vaporizing and ionizing organics without fragmenting
them, and because of the complicated mass spectra that are generated from
particles that contain mixtures of organics. This talk will focus on new
developments in instrumentation aimed at addressing some of these issues.
Thursday, February 14, 2008
Dr. Jian-Qiao Sun
Professor, Ph.D., P.E., ASME Fellow
School of Engineering
University of California, MercedSmart Physical Rehabilitation Devices and Their Controls
As the medical expenses grow faster, there is a need for inexpensive, small and intelligent rehabilitation devices that are suitable for home use or for small clinic. Smart materials, advanced electronics and modern control theory can offer such solutions for various rehabilitations. This seminar presents recent studies of rehabilitation devices including smart knee braces, variable resistance exercise devices and smart knee ankle braces. These devices are designed for early gait training of stroke patients, and strength training of people with muscle injuries. Engineering research issues associated with smart rehabilitation devices are highlighted in the talk, in particular, real-time gait event detection algorithms, and adaptive controls for regulating the exercise device to provide prescribed resistance profile as a function of the joint angle for a given patient. The current studies suggest that the devices discussed here are merely three examples of many possible medical devices that engineers can develop for the well-being of the mankind.
Wednesday, March 12, 2008 - Special Seminar
Micro and Miniature Technologies of Advanced Energy and Thermal Systems
(Fuel Cells and Heat Pipes)
Amir Faghri
United Technologies Endowed Chair Professor in Thermal-Fluids Engineering
University of Connecticut
The 21 st century will see the development of a wide range of active miniaturized energy devices with application in energy management and power sources, electronic cooling, energy storage and bioengineering. Although these active devices are effective, they are often cumbersome and inefficient considering the auxiliary supporting devices such as pumps, fans, and other moving parts they require for operation. A more efficient and novel approach involves use of passive small energy and thermal devices with no moving parts. Two research thrusts will be presented in this talk.
We propose a new miniature passive direct methanol fuel cell (DMFC) that includes a fuel cell stack and ancillary systems with no moving parts. This system uses passive approaches for fuel storage and delivery, air breathing, water management, CO 2 release, and thermal management. The performance characteristics of the passive miniature DMFC system will be presented.
Increasing component densities of the integrated circuit (IC) and packaging level have led to serious challenges in thermal management problems in electric cooling. Micro heat pipes are one of the promising cooling devices because of their high efficiency, reliability and cost effectiveness. Theoretical and experimental analysis performed on micro and miniature heat pipe arrays reveals a 300% improvement in effective thermal conductivity at high heat fluxes over conventional approaches.
1003 Kemper Hall
Wednesday, March 12, 2008
2:10pm
Refreshments at 2:00!
Thursday, March 13, 2008
Dr. A. Khodadoust
Senior Manager, Boeing Phantom Works
Huntington Beach , California
Advanced Flight Technology Concepts at Boeing Phantom Works
Advanced Technology Concepts at Boeing cover a wide spectrum, ranging from low- to high-speed flight regimes. I will touch on high-lights in subsonic, supersonic and hypersonic flight technology development at Boeing Phantom Works. In subsonics, design of transport vehicles with extremely efficient fuel burn and ability to operate from short runways has been center of recent attention. I will highlight areas of development relative to the Blended Wing Body program, as well as technologies that are aimed at minimization or elimination of flow separation. In supersonics, design of aircraft with minimal sonic-boom footprint has seen a resurgence. Areas of research and development at Boeing will be described which show promise in improving our understanding of sonic boom control and mitigation. In hypersonics, design of next-generation spacecraft has been a topic of focus lately, with the presidential vision for space exploration. Interest in the design of Space Shuttle replacement has inspired the assessment of several vehicle shapes, suitable for atmospheric re-entry. Examples of research, development and design at Boeing in this topic area will be described.
Thursday, April 10, 2008
Jonathan R. Wolpaw,
M.D.
Chief, Laboratory of Nervous System Disorders
Wadsworth Center
New York State Department of Health and State University of New York
Brain-Computer Interfaces (Bcis) for Communication and Control
Brain-computer
interface (BCI) research seeks to develop new augmentative communication
and control technology for people with severe neuromuscular disorders, such
as amyotrophic lateral sclerosis (ALS), brainstem stroke, and spinal cord
injury. The goal is to give these users, who may be totally paralyzed ("locked
in"), basic communication and control capabilities so that they can
express their desires to caregivers or even operate word processing programs
or neuroprostheses. Current BCIs determine the intent of the user from scalp-recorded
electrical brain signals (EEG), or from electrodes surgically implanted
on the cortical surface (ECoG) or within the brain (neuronal action potentials
(spikes) or local field potentials (LFPs)). These signals are translated
in real time into commands that operate a computer display or other device.
Successful operation requires that the user encode commands in these signals
and that the BCI derive the commands from the signals. Thus, the user and
the BCI system need to adapt to each other initially and continually to
ensure stable performance. This dependence on the mutual adaptation of user
to system and system to user is a key principle of BCI operation.
Thursday, May 08, 2008
Marcel Ilie
Department of Mechanical and Aerospace Engineering
Carleton University
Ottawa , ON , Canada
Aerodynamic, Aeroacoustic and Aeroelastic Investigations
of helicopter Blade-Vortex Interaction
The Blade-Vortex Interaction (BVI) phenomenon is one of the main sources of noise and vibrations for helicopter, and comprises one of the most complex unsteady flow features of helicopter rotor in forward flight. In rotorcraft, BVI produces impulsive, high amplitude, undesired noise (BVI noise) by the unsteady fluctuations in the blade loading due to the rapid changes of the induced velocity formed during the interaction with the vortices shed from the advancing blades.
The numerical simulation of BVI has been a challenging one for the fact that most of the numerical techniques either tend to alter the characteristics of the vortex, before the blade-vortex interaction occurs or are not able to capture all the fluctuations of the aerodynamic coefficients.
Aerodynamic, aeroacoustic and aeroelastic numerical investigations of Blade–Vortex Interaction have been conducted, using Large Eddy Simulation (LES). The simulations were performed for a subsonic flow, M = 0.3 and Reynolds number, Re = 1.3x10 6 based on the NACA 0012 airfoil chord length, c = 0.2 m. The effects of aeroelastic response of the blade, blade-vortex vertical miss-distance, angle of attack and vortex strength and vortex core size on the blade-vortex mechanism of interaction were investigated.
It was observed that the aeroelastic response of the blade, the blade-vortex vertical miss-distance, the angle of attack and the vortex strength and vortex core size, have a significant influence on the vortex-airfoil mechanism of interaction and implicitly on the aerodynamic coefficients and acoustic field.
The results of a comprehensive analysis will be presented in detail.