Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 08, 2024 - September 11, 2024
Among various driving forces of longitudinal ventilation flow, we know “natural air flow”. This is related to pressure difference between both portals caused by meteolorogical conditions, but it seems that the phenomena is sometimes not understood appropriately. The author describes definition of this phenomena firstly. Consideration is done on what happens due to differene in altitude of both portals, and explains the importance of measurement of natural air flow in tunnels before public service. Discussion is led also on the measurement of pressure difference in tunnel, where bouyancy effect can affect accuracy.