Flow visualization and determination of temperature distribution in inclined channels

Sağlamcı, Abdülaziz Mehmet
Subway transportation systems play an important role in human life in this century. Millions of people make use of subway transportation every day in metropolises. In subways, there is a very crucial situation "case of fire and smoke generation" that must be prevented. In subway areas, it is known that stairs are used to connect the ground with the subway area, metro stations in other words. Stairs have an angle with the ground horizontal called as tilt angle. The most important case of smoke movement in case of a fire occurs in the area of the subway constructions as being fresh air access for people. Originating a metro tunnel and simulating the case of fire, the objective of this thesis is to understand the smoke flow and temperature distribution characteristics in a combined tunnel composed of horizontal and inclined parts. Many researches have been made so far to lower the risk of poisoning cases due to smoke.In this study, both experimental and numerical investigations were made having larger tilt angles for the inclined parts of the domain varying from 25 to 40 degrees.The smoke flow patterns were observed by means of a CFD (Computational Fluid Dynamics) program.Velocity fields and the temperature distributions were investigated through the tunnel. In experiment, a controlled fire was started by burning mixture of propane-butane mixture and temperature distribution data was collected throughout the experimental tunnel using thermocouples attached in six planes located in the setup cross-sections. The experimental results were used to verify the CFD solution. Temperature trends shows indicative manner so that velocity profiles were investigated numerically. Effects of the ventilation velocity, inclination angle and fire location on the temperature and velocity profiles in the tunnel were investigated.


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Citation Formats
A. M. Sağlamcı, “Flow visualization and determination of temperature distribution in inclined channels,” M.S. - Master of Science, Middle East Technical University, 2018.