Electrode material release during high voltage breakdown Final technical report

Electrode material release during high voltage breakdow

G band atmospheric radars: New frontiers in cloud physics

Clouds and associated precipitation are the largest source of uncertainty in current weather and future climate simulations. Observations of the microphysical, dynamical and radiative processes that act at cloud scales are needed to improve our understanding of clouds. The rapid expansion of ground-based super-sites and the availability of continuous profiling and scanning multi-frequency radar observations at 35 and 94 GHz have significantly improved our ability to probe the internal structure of clouds in high temporal-spatial resolution, and to retrieve quantitative cloud and precipitation properties. However, there are still gaps in our ability to probe clouds due to large uncertainties in the retrievals. The present work discusses the potential of G band (frequency between 110 and 300 GHz) Doppler radars in combination with lower frequencies to further improve the retrievals of microphysical properties. Our results show that, thanks to a larger dynamic range in dual-wavelength reflectivity, dual-wavelength attenuation and dual-wavelength Doppler velocity (with respect to a Rayleigh reference), the inclusion of frequencies in the G band can significantly improve current profiling capabilities in three key areas: boundary layer clouds, cirrus and mid-level ice clouds, and precipitating snow. © 2014 Author(s)

Application of Inverse Models for Long-Term-Energy-Monitoring in the German Enbau: Monitor Project

in order to pave the way for energy savings and utilizing solar energy in non residential buildings, the german federal ministry of economics and technology (bmwi) has established an energy research program called "energy optimized building" that supports the planning and evaluation of demonstration projects. enbau:monitor, as the related accompanying project, documents and analyzes these projects on a common platform. in the framework of enbau:monitor, two different monitoring phases were defined. a detailed monitoring takes place during the first two years of operation. after this period a long-term energy monitoring was established in order to evaluate the sustainability of the innovative designs and systems. fraunhofer ise defined enhanced guidelines for the long-term-energy-monitoring and developed a system for prescription of the placement of meters. furthermore the application of inverse models for automated control of the energy use connected to heating, cooling and electricity is envisaged. the paper presents the new concept as well as the most important findings of the enbau:monitor project

HTR2008-58178 TH3D, A THREE-DIMENSIONAL THERMAL HYDRAULIC TOOL, FOR DESIGN AND SAFETY ANALYSIS OF HTRS HTR2008-58178

ABSTRACT The institute of nuclear engineering and energy systems (IKE), University of Stuttgart, Germany has developed a new thermal hydraulic tool which can be used for three-dimensional thermal hydraulic analysis of pebble bed as well as block type HTRs. During nominal operation, the flow inside the gas-cooled High Temperature Reactor is essentially INTRODUCTION Considering some criterion like optimal use of natural resources, proliferation resistance, nuclear safety excellence, cost saving, satisfying broader requirements (hydrogen production, desalination) etc, six systems are selected by the Generation IV International Forum as 4th generation nuclear system and two of the chosen six systems are gas cooled system [1]. The high temperature gas cooled reactor is considered as one of the most promising generation IV reactors due to its inherent safety performance as well as its high conversion efficiency due to higher outlet coolant temperature. For the assessment of the feasibility and safety of generation IV HTRs, reliable tools for simulating heat transfer and fluid flow (coupled with neutronics) inside the reactor core must be available. With the rapid development of computing power, also three dimensional simulations can be performed, since one dimensional or two dimensional simulation tools used so far seem not to be adequate for addressing non axis-symmetric situations arising from non axis-symmetric fuelling/defuelling, burnup, partial blockage of coolant channels in block fuel or from non axis-symmetric geometrical conditions (e.g. AVR reactor). As it is mentioned in our previous pape