ENERGY -- Designing tomorrow's water heater . . .
Consumers and the environment could ultimately be the beneficiaries of a high-efficiency CO2 heat pump water heater concept being researched by General Electric and Oak Ridge National Laboratory. Through a cooperative research and development agreement, GE and ORNL are designing a prototype residential water heater that will feature an energy factor of greater than 2.0 with a first hour rating of more than 50 gallons. If the design proves to be technically and economically viable, it could ultimately result in a commercial product. This level of performance would exceed Energy Star standards established for water heaters. The key to the design is the benign nature of the refrigerant and the high efficiency potential that can be achieved using CO2, a natural refrigerant with no associated emissions. A previous ORNL-GE collaboration resulted in a hybrid electric water heater for new and existing homes. [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
DETECTORS -- Saving lives . . .
About 2,500 people still die each year in residential fires, but that number could be reduced with a smart fire alarm that can immediately distinguish between fires and nuisances. A team led by Oak Ridge National Laboratory's Bruce Warmack of the Measurement Science and Systems Engineering Division is developing such an alarm. Warmack's cognitive alarm incorporates a microcontroller that utilizes a mathematical technique called linear discriminant analysis. This feature adds less than $1 to the cost but makes the alarm far more effective. The new alarm also features a carbon monoxide detector and an alert that sounds at a lower frequency shown to be more effective at awakening youngsters and the elderly. This research is being done at the request of the U.S. Fire Administration and the Consumer Product Safety Commission. [Contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
SUPERCONDUCTORS -- Surprising transitions . . .
Neutron scattering experiments performed on iron-based superconducting material at Oak Ridge National Laboratory and Canada's Chalk River Laboratories have unveiled surprising changes in the materials' subatomic structural and magnetic properties when subjected to relatively low pressures. The experiments on barium iron arsenide crystals revealed changes in spin-ordering and phase transitions that offer insight into the dynamics that enable high-temperature superconductivity. Boston University researcher Stephen Wilson, lead author of the Physical Review Letters paper, cited the triple-axis spectrometer at ORNL's High Flux Isotope Reactor along with the laboratory's high-quality crystal fabrication capability in the success of the experiments. "In general, the world-class instruments at HFIR and the high neutron flux there make difficult experiments like this one possible," Wilson said. [Written by Bill Cabage; media contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
PHYSICS -- ORNL scores six papers . . .
The Journal of Condensed Matter Physics has put out a special issue on the dynamics of water and glass-forming liquids that features six ORNL neutron sciences research collaborations. The special issue focused on fluids and other soft condensed materials confined in matrices, a natural area for neutron scattering investigations. The primary goal is to understand the fundamental physics behind why a liquid would freeze or not freeze under given conditions. Primary instruments for such studies are the Spallation Neturon Source's Backscattering Spectrometer, the Neutron Spin Echo Spectrometer and the Nanoscale-Ordered Materials Diffractometer. [Written by Agatha Bardoel; media contact: Ron Walli, 865-576-0226; wallira@ornl.gov]
SUPERCONDUCTIVITY -- VULCAN delivers . . .
Neutron testing of the Japanese-made superconducting cable for the Central Solenoid magnetic system for U.S. ITER has been done at the Spallation Neturon Source's VULCAN Engineering Materials Diffractometer. The 3-meter cable, mounted in a specially designed cryostat, can be cooled down to minus-193.5 degrees Celsius. The mapping experiment was performed at room temperature and cryogenic conditions. Past conductor performance tests have shown the cable degrades under cyclic power loading conditions. VULCAN can measure the strain on the superconducting niobium tin (Nb3Sn) phase, inside the metal jacket that encloses the cable. It is the only neutron scattering instrument capable of combining temperature, magnetic fields and sample size with rapid data accumulation. [Written by Agatha Bardoel; media contact: Ron Walli, 865-576-0226; wallira@ornl.gov]