Objective
A SERIES OF FULL-SCALE AEROSOL-DIFFUSION EXPERIMENTS, REPRESENTATIVE FOR RADIONUCLIDE BEHAVIOUR IN THE ENVIRONMENT, ARE PROPOSED FOR RATIONAL EVALUATION OF MODELLING UNCERTAINTIES IN ATMOSPHERIC DISPERSION MODELS USED IN PROBABILISTIC ACCIDENT CONSEQUENCE CODES.
CURRENTLY USED ATMOSPHERIC DISPERSION MODELS SHOW A LARGE SPREAD IN THEIR RESULTS FOR THE NEAR-SITE REGION. THIS CALLS FOR FULL-SCALE STUDIES OF FLUCTUATING PLUME CONCENTRATIONS SUPPORTED BY A FULL COMPLEMENT OF METEOROLOGICAL MEASUREMENTS. THESE ARE NEEDE FOR THE IDENTIFICATION AND ESTIMATION OF THE MAJOR CONTRIBUTORS TO THE EXPECTED OVERALL MODELLING UNCERTAINTIES, INCLUDING THE INHERENT NATURAL UNCERTAINTY IN CONCENTRATION PREDICTIONS AND SAMPLING TIME EFFECTS.
Full scale diffusion experiments with continuous, surface releases of submicron aerosol plumes were conducted. For a variety of different atmospheric stability and wind conditions, measurements were obtained of the ground level, cross wind plume concentration profile, with high spatial (1.5 m) and temporal (3 s) resolution using light detection and ranging (LIDAR). Statistics of the concentration fluctuations across the plume have been investigated. In particular, we have distinguished between fixed and moving frame statistics, in order to differentiate between absolute and relative type diffusion. This borex database provides the radiation protection programme with a series of near site reference dispersion experiments in which the inherent, naturally occurring fluctuation levels have been investigated. It establishes a reference for intercomparison and evaluation of near site atmospheric dispersion models.
IT IS PROPOSED TO ESTABLISH A NEAR-REGION DATABASE FOR ATMOSPHERIC DISPERSION, CONSISTING OF NEAR-GROUND MEAN AND MEAN-SQUARE HORIZONTAL CONCENTRATION PROFILES FROM MEASUREMENTS OF DETAILED CONCENTRATION FLUCTUATIONS WITH HIGH SPACE AND TIME RESOLUTION. THE INCLUSION OF IMPORTANT METEOROLOGICAL MEASUREMENTS WILL ESTABLISH THE INFORMATION NECESSARY FOR SUBSEQUENT EVALUATION OF ATMOSPHERIC DISPERSION MODELS WITH RESPECT TO THEIR PREDICTABILITY AT DIFFERENT DOWNWIND DISTANCES, AND AT DIFFERENT ATMOSPHERIC STABILITY-CATEGORIES.
IN ADDITION TO THE COLLECTING OF A COMPLETE SET OF METEOROLOGICAL SURFACE LAYER PARAMETERS, THE MOST IMPORTANT DATA IN THE PROPOSED RESEARCH WILL BE BASED ON REMOTE PLUME-CONCENTRATION PROFILES USING A DFVLR-MINILIDAR SYSTEM. ITS PRINCIPLE OF OPERATION IS SIMILAR TO THAT OF A RADAR: PULSED LASER RADIATION IS TRANSMITTED INTO AN ARTIFICIAL PRODUCED AEROSOL SMOKE PLUME, AND BACK-SCATTERED LIGHT RETURNS INTO A TELESCOPE WITH A PHOTO-DETECTOR. THE TIME BETWEEN TRANSMISSION AND RECEPTION OF A LIGHT PULSE INDICATES THE RANGE FROM THE LIDAR, AND THE INTENSITY OF THE BACK-SCATTERED SIGNAL CAN UPON DATA-PROCESSING BE RELATED TO THE INSTANTANEOUS CONCENTRATION.
METEOROLOGICAL MEASUREMENTS WILL SIMULTANEOUSLY BE TAKEN BOTH AT THE SOURCE POINT AND, AT A REPRESENTATIVE POINT DOWNSTREAM FROM TWO 10-METER HIGH MASTS, EACH EQUIPPED WITH A 3-DIMENSIONAL SONIC ANEMOMETER-THERMOMETERS CONNECTED TO ONLINE FAST-SCANNING DATA ACQUISITION SYSTEMS. THESE SYSTEMS PROVIDE 10-MINUTE AVERAGE VALUES OF THE MEAN WIND SPEED AND DIRECTION IN ADDITION TO THE CO-VARIANCE MATRIX OF THE WIND COMPONENTS U, V, W AND TEMPERATURE T. IMPORTANT QUANTITIES SUCH AS INTENSITIES, SHEAR STRESS AND HEAT FLUXES FOR DETERMINATION OF THE TURBULENCE LEVEL AND THE ATMOSPHERIC STABILITY IS THEREBY PROVIDED. IN ADDITION, ANALOG RECORDING OF THE SIGNALS WILL BE PERFORMED FOR SUBSEQUENT DIGITIZING AND SPECTRAL ANALYSIS, AND ALSO FOR PLUME ADVECTION IN CERTAIN TYPES OF DISPERSION MODELS.
FLAT HOMOGENEOUS EXPERIMENTAL SITES, REPRESENTATIVE OF THE TERRAIN TREATED BY NEAR-SITE ATMOSPHERIC DISPERSION MODELS, WILL BE SELECTED FROM PREFERRED LOCATIONS AT THE BORRIS MOORS (DENMARK) OR ALTERNATIVELY AT MEPPEN (FEDERAL REPUBLIC OF GERMANY).
A POWERFUL AND STURDY ARTIFICIAL SMOKE GENERATOR WILL PRODUCE CONTINUOUS NON-TOXIC WHITE SMOKE PLUMES OF SUB-MICRON AEROSOLS (CONSISTING OF CONGLOMERATED SIO2 AND NH4 MOLECULES) THAT IS EASILY DETECTABLE BY THE LIDAR. LIDAR-MEASUREMENTS OF THE CROSS-WIND GROUND-LEVEL CONCENTRATION PROFILES WILL TAKE PLACE AT THE DOWNWIND DISTANCES 31.25 M, 62.5 M, 125 M, 250 M, 500 M, 1 KM, 2 KM, 4 KM AND POSSIBLY ALSO AT 8 KM.
SONIC ANEMOMETERS, PLACED 10 M ABOVE THE GROUND BOTH AT THE SOURCE LOCATION AND ALSO AT A REPRESENTATIVE LOCATION DOWNWIND, WILL ACHIEVE FULL DOCUMENTATION OF BOTH THE MEAN FLOW AND OF THE TURBULENCE FIELDS. SIMULTANEOUSLY CONDUCTED SF6-TRACER DISPERSION EXPERIMENTS WILL PLAY AN IMPORTANT ROLE IN OBTAINING THE BEST POSSIBLE ABSOLUTE CALIBRATION OF THE LIDAR.
SELECTED EXPERIMENTS WILL BE ACCOMPANIED BY AERIAL PHOTOGRAPHS OF THE VISIBLE SMOKE-PLUME, A TECHNIQUE THAT EARLIER HAS PROVEN POWERFUL FOR VISUALISATION OF THE INSTANTANEOUS HORIZONTAL PLUME OUTLINE.
FOLLOWING INITIAL LIDAR-CALIBRATION EXPERIMENTS, IT IS INTENDED TO CONDUCT TWO EXTENSIVE EXPERIMENTAL CAMPAIGNS, ONE TO TWO WEEKS DURATION EACH, PREFERABLY AT TWO DIFFERENT SEASONS. EXPERIMENTS, EACH OF SEVERAL HOURS CONTINUOUS DURATION, WILL START THROUGHOUT THE DAY (MORNING, NOON, AFTERNOON, EVENING) IN ORDER TO COVER AS MANY DIFFERENT STABILITY-CATEGORIES AS POSSIBLE.
Fields of science (EuroSciVoc)
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
- natural sciences computer and information sciences databases
- engineering and technology electrical engineering, electronic engineering, information engineering electronic engineering sensors optical sensors
- engineering and technology electrical engineering, electronic engineering, information engineering information engineering telecommunications radio technology radar
- natural sciences physical sciences optics laser physics pulsed lasers
You need to log in or register to use this function
Programme(s)
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Topic(s)
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Data not available
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Call for proposal
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Data not available
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Funding Scheme
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Coordinator
4000 ROSKILDE
Denmark
The total costs incurred by this organisation to participate in the project, including direct and indirect costs. This amount is a subset of the overall project budget.