Accident simulation

Accident simulation Large-scale accidents normally cannot be staged for experimental purposes. It is impossible to put a building on fire in order to see how smoke spreads. In this case, numerical simulation is the sensible approach. 

Those attending the accident simulation were able to see, from various vantage points, the action of the Station Emergency Teams dealing with the accident situation. 

In order to determine the minimum requirements for fulfilling a success criterion (e.g. 75 % of pump flow must be available for sufficient cooling) frequently information from accident simulations is used, which have been carried out in other contexts, e.g. the licensing procedure. The event tree analysis for the technical systems of a plant may be divided into two tasks ... 

The contents of the paper includes results from inherent research project of MOERI/KORDI Development of Ship Safety Performance Prediction Technology for Cost Benefit Analysis and results from Marine Transportation Accident Simulation Analysis and Preventive Measure Development project funded by Korea Radioactive Waste Management Corporation. 

The next evolution of the method presented by Busch is called PreEffect-iFGS. It is a prospective method for evaluating the field effectiveness of integral pedestrian protection systems [21]. The main procedures of Busch, i.e., selection of relevant accidents, simulation with/without system, translation into injury severity, and calculation of the effectiveness, stayed the same with some additions. The improvement is an incorporation of test results for active and passive safety systems derived from hardware testing [54]. The initial version also includes an automated backwards simulation of each accident based on the values available in GIDAS. The results are then transferred into the commercial software PC-Crash and are then simulated forward with and without the measure in question. 

Burst operation will allow extension of the measurements with SHEBA to a wider range of accident simulations. 

SHEBA continues to be a valuable tool for dosimeter evaluation, accident simulation, and student instniction. 

Zeyen, R., Poss, G., Clement, B. A spectral light extinction photometer for the characterisation of nuclear aerosols in the containement of the Phebus FP integral severe accident simulating experiment. Paper presented at the AAAR % (American Association for Aerosol Research), Orlando, 1996... 

SAPHER, D., DZODZO, M, GREENSPAN, E., Applying the DSNP modular modelling system to transient and accident simulations of lead cooled reactors, ICONE-9 (Proc. 9 Int. Conf on Nuclear Engineering, Nice, France, April 8-12, 2001), ICONE9-661, ASME. 

Nearly full-scale worst accident simulation tests can be carried out to obtain licensing before commercial operation (demonstrable safety) to convince the public and the regulators of this safety concept. Safety demonstration by accident simulation tests can be, and shall be, requisite in licensing of the GTHTR300. 

Comparison of the measured isotope distributions with simulation data is carried out within the framework of the models corresponding to various developments, accompanied accident of 1986. Estimations of characteristics of physical influence (temperature, etc.) to which ChAPS s concrete stmcture have been undergone are discussed. 

The model contains a surface energy method for parameterizing winds and turbulence near the ground. Its chemical database library has physical properties (seven types, three temperature dependent) for 190 chemical compounds obtained from the DIPPR" database. Physical property data for any of the over 900 chemicals in DIPPR can be incorporated into the model, as needed. The model computes hazard zones and related health consequences. An option is provided to account for the accident frequency and chemical release probability from transportation of hazardous material containers. When coupled with preprocessed historical meteorology and population den.sitie.s, it provides quantitative risk estimates. The model is not capable of simulating dense-gas behavior. 

Nichols, B. D. and W. S. Gregory, 1986, FIRAC User s Manual A Computer Code to Simulate Fire Accidents in Nuclear Facilities, NUREG/CR-4561 (LA-10678-M), LANL, April. 

Accidental vapor cloud explosions do not occur under controlled conditions. Various experimental programs have been carried out simulating real accidents. Quantities of fuel were spilled, dispersed by natural mechanisms, and ignited. Full-scale experiments on flame propagation in fuel-air clouds are extremely laborious and expensive, so only a few such experiments have been conducted. 

Hjertager, B. H., T. Solberg, and J. E. Fprrisdahl. 1991b. Computer simulation of the Piper Alpha gas explosion accident. ... 

Simulation of a fire resulting from a transport accident in a cross wind. The flame is visualized in yellow/red, while soot clouds are represented in black. (From Tieszen, S., private communication.)... 

Margolis, S. G., and J. A. Redfield, 1965, FLASH A Program for Digital Simulation of the Loss of Coolant Accident, WAPD-TM-534, Bettis Atomic Power Lab., Pittsburgh, PA. (6)... 

Accidental slow addition of water to a mixture of the anhydride and acetic acid (85 15) led to a violent, large scale explosion. This was simulated closely in the laboratory, again in the absence of mineral-acid catalyst [1]. If unmoderated, the rate of acid-catalysed hydrolysis of (water insoluble) acetic anhydride can accelerate to explosive boiling [2], Essentially the same accident, fortunately with no injuries or fatalities this time, was repeated in 1990. 

Hatoum et al., 1990) and may, in fact, better simulate possible workplace accidents and provide additional information. 

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