David K. Irick

Collaborative Spectrum Sensing in Cognitive Radio Vehicular Ad Hoc Networks: Belief Propagation on Highway

Cognitive radio technique is applied to Vehicular Ad hoc Networks (VANET) to increase frequency bandwidth. Spectrum sensing for opportunistic spectrum access is carried out collaboratively among neighboring vehicles. For the collaborative spectrum sensing, Belief Propagation (BP) is applied to tackle the distributed observations and to exploit redundancies in both space and time. The corresponding performance is analyzed for a three-vehicle case and is demonstrated using numerical simulations.

Emission Performance of Selected Biodiesel Fuels

Because of the great interest in biodiesel fuels around the world, the International Energy Agencys Committee on Advanced Motor Fuels sponsored this project to determine emissions and performance of a number of biodiesel fuels with a special emphasis on unregulated emissions. Oak Ridge National Laboratory (ORNL) and Technical Research Centre in Finland (VTT) carried out the project with complementary work plans. Several different engines were used between the two sites, and in some cases emissions control catalysts were used, both at ORNL and at VTT. ORNL concentrated on light and medium duty engines, while VTT emphasized a heavy-duty engine and also used a light duty car as a test bed. Common fuels between the two sites for these tests were rape methyl ester in 30% blend and neat, soy methyl ester in 30% blend and neat, used vegetable oil methyl ester (WOME) in 30% blend, and the Swedish environmental class 1 reformulated diesel (RFD). ORNL used ASTM 2D diesel as baseline, while VTT used EN 590 (European diesel) as the base. VTT also tested a blend of 30% UVOME with RFD. Steady state test cycles were used for all engines and fuels except for the light duty vehicle, which was tested on a chassis dynamometer using the US FTP 75 test. Results are presented for regulated emissions as well as for aldehydes and composition of particulate matter, and polyaromatic hydrocarbons. VTT also produced results of Ames tests on the mutagenicty of samples of particulate matter. Generally, the biodiesel fuels had higher NO x emissions but lower values of HC, CO, and particulates. Unregulated emissions varied greatly between fuels and engines.

Stabilizing Excessive EGR With an Oxidation Catalyst on a Modern Diesel Engine

For diesel engines (CIDI) the excessive use of exhaust gas recirculation (EGR) can reduce in-cylinder oxides of nitrogen (NOx) generation dramatically, but engine operation can also approach zones with high instabilities, usually accompanied with high cycle-to-cycle variations and deteriorated emissions of total hydrocarbon (THC), carbon monoxide (CO), and soot. A new approach has been proposed and tested to eliminate the influences of recycled combustibles on such instabilities, by applying an oxidation catalyst in the high-pressure EGR loop of a turbocharged diesel engine. The testing was directed to identifying the thresholds of stable operation at high rates of EGR without causing cycle-to-cycle variations associated with untreated recycled combustibles. The elimination of recycled combustibles using the oxidation catalyst showed significant influences on stabilizing the cyclic variations, so that the EGR applicable limits are effectively extended. The attainability of low NOx emissions with the catalytically oxidized EGR is also evaluated.Copyright

Effect of Chrome Coating on Resistance of Sintered Joint for ITER Central Solenoid

The ITER Central Solenoid has 36 interpancake joints. The joints are required to have a resistance below 4 nOhm at 45 kA at 4.5 K. The US ITER Project Office developed and qualified a sintered joint for the interpancake joints that consistently showed exceptionally low dc resistance of 0.13 nOhm at up to 80 kA in the self-field of about 1.5 T. To provide a good current distribution in the joint, we removed chrome plating from the strands in this area. We built and tested four samples of the sintered joints before 2012. Such a low resistance prompted an investigation of the possibility of leaving the chromium on the strands during the joint preparation and still staying well below allowable resistance. Although removal of the chrome plating is not a very labor-intensive or time-consuming operation, it requires handling of harmful fumes and produces a solution containing hexavalent Cr, which is a hazardous substance. Elimination of the Cr removal step is a simplification of the fabrication process and therefore is a desirable act. We built two identical racetrack samples of the sintered joint and tested them in our joint test apparatus. One sample had Cr removed from the strands, the other had Cr intact. This paper provides a description of the test samples, fabrication steps, and results of the dc resistance measurements.

The effects of glass weave on the low temperature flexure properties of composite laminates

A variety of glass fiber weaves are being considered for use in insulation materials in the International Thermonuclear Experimental Reactor central solenoid. In this study, three candidate glass weaves (1581, 7781, and 38050) were used with a Di-Glycidyl Ether of Bisphenol F (DGEBF) anhydride epoxy matrix to produce composite laminates of constant thickness. These laminates were compared at room temperature (295 K) and liquid nitrogen temperature (77 K) via three-point flexure tests. The material variables among these glass products were type of weave pattern (eight-harness satin versus plain), fiber surface treatment (epoxy compatible surface treatment versus no treatment), and cloth areal density. Based on the flexural elastic modulus and strength data at both 77 K and 295 K, the 7781/epoxy composites showed the highest values followed closely by 1581/epoxy. The 38050/epoxy performed quite poorly. The correlations of the laminate density with modulus and strength at both temperatures were almost linear. It was also found that the failure modes of samples having fibers with epoxy compatible surface treatment differed from those having no surface treatment.

R&D effort for ITER Central Solenoid

The US ITER organization is responsible for supply of the Central Solenoid (CS) to the ITER collaboration. This 1,000 t object is the largest pulsed superconducting magnet ever built.

The University of Tennessee EcoCAR 2 Communications, Outreach, Education and STEM Recruiting Program Overview: Year 2

The U.S. Department of Energy’s (DOE) Advanced Vehicle Technology Competition (AVTC) series is a long running collegiate vehicle design competition for North American universities. The current three year competition series, known as EcoCAR 2: Plugging In To the Future, has students design and build a hybrid electric vehicle (HEV) that also incorporates alternative fuel. Teams are donated a 2013 Chevrolet Malibu by General Motors to modify. A significant aspect of the competition series is the public outreach and education aspect that leverages the expertise of the students in advanced vehicle technologies and alternative fuels. This also highlights the systems level approach to integrating all aspects of the vehicle to build a vehicle that has the best possible fuel economy, lowest well-to-wheel greenhouse gas emissions and lowest criteria air pollutant emissions while maintaining or exceeding vehicle performance, utility and safety. This paper presents an overview of the University of Tennessee’s (Team Tennessee) EcoCAR 2 outreach program, including core program goals and measures of effectiveness of the program for Year 2 of the competition. The paper focuses on the role that such programs can have on effective science, technology, engineering and mathematics recruiting through an overview of the outreach activities and the integration of hands on activities and partnerships with local schools. The leveraging of outreach and education capabilities with the team’s outreach partners is also highlighted.Copyright

Graduate Automotive Technology Education (GATE) Center

The Graduate Automotive Technology Education (GATE) Center at the University of Tennessee, Knoxville has completed its sixth year of operation. During this period the Center has involved thirteen GATE Fellows and ten GATE Research Assistants in preparing them to contribute to advanced automotive technologies in the centers focus area: hybrid drive trains and control systems. Eighteen GATE students have graduated, and three have completed their course work requirements. Nine faculty members from three departments in the College of Engineering have been involved in the GATE Center. In addition to the impact that the Center has had on the students and faculty involved, the presence of the center has led to the acquisition of resources that probably would not have been obtained if the GATE Center had not existed. Significant industry interaction such as internships, equipment donations, and support for GATE students has been realized. The value of the total resources brought to the university (including related research contracts) exceeds

A Preliminary Investigation into the Mitigation of Plug-in Hybrid Electric Vehicle Tailpipe Emissions Through Supervisory Control Methods

4,000,000. Problem areas are discussed in the hope that future activities may benefit from the operation of the current program.