Open AccessTurbulent thermal characteristics and air flow patterns in a naturally ventilated tunnel with roof openings
Author(s) -
A. Mason,
R. Harish
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1716/1/012026
Subject(s) - turbulence , roof , ventilation (architecture) , airflow , mechanics , environmental science , flow (mathematics) , mass flow , meteorology , thermal mass , heat transfer , reynolds number , large eddy simulation , smoke , thermal , marine engineering , geology , engineering , physics , mechanical engineering , structural engineering
Air flow is a major characteristic in the tunnel ventilation design, to avoid severe disasters like smoke suffocation problems in tunnel and fire accidents. Tunnels are best ways to reduce distance between two adjacent places. It may be underground or above ground, depending upon the usage of it. There are different types of tunnel ventilation, e.g. roof vents, side vents, mechanical ventilation, naturally ventilated etc. This paper majorly focuses on roof vents mass extraction with different sizes of the heat sources and it also records the horizontal and normal velocity for different sizes of heat sources. The Reynolds Number is low but still turbulence occurs when we deal with buoyant smoke keeping density as incompressible ideal gas. Ratio of height by width is taken into account and the transient air flow is simulated for 10 seconds, and mass flow is recorded at each time step of 0.1 seconds using Large Eddy turbulence Model to capture the flow physics. It is observed that with changing the heat source size, mass flow rate from each vent changes significantly and it drastically affects the air flow patterns and heat transfer characteristics inside the tunnel.