Volume 19, Issue 12 (December 2019)                   Modares Mechanical Engineering 2019, 19(12): 3083-3093 | Back to browse issues page

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Taheri M, Afzalian M, Zolfaghari S, Hassanzadeh H. Air Inlet Angle Effects in Swirling Diffuser of UFAD Systems on Micron Particles Pattern Distribution. Modares Mechanical Engineering 2019; 19 (12) :3083-3093
URL: http://mme.modares.ac.ir/article-15-26284-en.html
1- MSc Mechanical engineering, University of Birjand
2- Ph.D candidate, University of Birjand
3- Associate professor, Department of Mechanical Engineering, University of Birjand , zolfaghari@birjand.ac.ir
4- University of Birjand
Abstract:   (4905 Views)
Particle pollutants in the indoor environment are a serious threat to human health. Therefore, it is necessary to recognition, investigation, and controls of the distribution of these particles in the indoor environment. In the present research, the effect of air inlet angle of swirling diffusers in UFAD systems has been investigated on micron particles pattern distribution by considering the thermal comfort condition. For analyzing the fluid flow and particle distribution, the development of OpenFoam solver by the Eulerian-Lagrangian method has been used. The two-node model of Gauge has been used for predicting the thermal comfort conditions. Inlet angles are set in three cases of 30, 45 and 60. Based on the results, in all three cases, the TSENS index is in the thermal comfort zone. However, by changing the swirling angle from 30 to 60, the vertical temperature difference can be reduced about 1℃. Investigation of changing the inlet angle shows that at inlet angle of 30 and 60 degrees, the percentage of particles exited with 2.5 micrometers diameter were 32% and 55% of the total particles, respectively. In other words, increasing the inlet air angle can lead to exit more amount of any size of particles from the room. In addition, by increasing particles size, larger particles removed faster from the breathing zone, and smaller particles will remain longer time in the air. Therefore, smaller particles have a greater impact on indoor air quality.
Full-Text [PDF 1230 kb]   (1769 Downloads)    
Article Type: Original Research | Subject: Plumbing & Air Conditioning
Received: 2018/10/18 | Accepted: 2019/05/26 | Published: 2019/12/21

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