Combination of three different measurement techniques to investigate the combustion aerosol from an oil fire test in a nuclear power plant

In nuclear power installations combustible materials are abundant, as e.g. electrical cable insulations, lubrication greases and oils. Under certain circumstances the fire load may become considerable. The behavior and consequences of fires in a containment was subject of investigation in a series of fire experiments which were conducted in the frame of the Heiβdampf-Reaktor-Sicherheitsprogramm (HDR Safety Project) in 1990 (Katzenmeier, 1990). The decommissioned HDR power reactor plant in Kahl was used for these experiments, its full scale size allows a simple application of the experimental results to other power plants. In the experiments E41.5-E41.10 described in this article a low soot grade isoparaffin oil served as combustible material. It was burned in a 100 m3 compartment located in the mid plane of the HDR reactor containment. The development of the fire, its progression and the thermal-hydraulic impact on the building and the installations were measured. In parallel a code calculation exercise is foreseen to compare different fire codes with the experimental data. The soot aerosol developed during the first is an additional hazard for the vent systems and for the personnel in possible intervention actions. Therefore, beginning with experiment E41.5, the aerosol concentration was measured at three different locations in the containment. To improve the reliability of the results three different types of aerosol measurement instrumentation were used. In this paper the aerosol measurements and the results will be presented. (author)