Evaluation of water transport behaviorin Sodium fire experiment - II

Nakagiri, Toshio  

Evaluation of water transport behavior in Sodium Fire -II (Run-D4) was performed. Results of other experiments performed in Oarai-Engineering Center were considered in the evaluation, and the results of the evaluation were compared with the calculated results of ASSCOPS code. The main conclusions are described below. (1)lt was estimated that aerosol hydrates were not formed in the test cell in the experiment, because of high gas temperatures (200C300C), but water vapor absorption by the formation of aerosol hydrates and water vapor condensation were occurred in humidity measure line, because of low gas temperature (20C 40C). Therefore, it was considered appropriate that measured water vapor concentration in the humidity measure line was different from the real concentration in the test cell. (2)Water vapor concentration in the test cell was assumed to be about 35,000 ppm during sodium leak, and reached to about 70,000 ppm because of water release from heated concrete (over 100C) walls after 190 min from sodium leak started. The assumed value of about 35,000 ppm during sodium leak almost agree with assumed value from the quantity of aerosol in the humidity measure line, but no support for the value of about 70,000 ppm after 190 min could be found. Therefore, water release rate from heated concrete wans can change with their temperature history.