Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 05, 2021 - September 08, 2021
To reduce greenhouse gas emissions, ammonia, which does not emit carbon dioxide when burned, is expected to be used as a fuel for thermal power generation and ships. From the viewpoint of safe use, the behavior of gas flow during ammonia leakage is investigated. The ammonia leakage instead of hydrogen is simulated by FDS (Fire Dynamics Simulator) in the same computational situation as the previous simulation that reproduced the Hallway model hydrogen leakage experiment. The leakage volume is 57 L/min, the same as that for hydrogen, and is allowed to leak for 600 seconds from the start of the calculation. Simulations are performed with natural ventilation through the ceiling and side wall openings, and with forced exhaust ventilation using a ventilator installed in the ceiling opening. The leaked ammonia reaches the ceiling, shows high concentration near the ceiling, and is discharged outside through the ceiling opening. At the same time, air is flowing in through the opening on the right side wall. In the case of natural ventilation, the concentration of ammonia near the ceiling is about 7%. This concentration, in the case of forced ventilation, is shown to be as high as 12% when the ventilation rate is low, but decreases significantly as the ventilation rate increases.
