Investigation of the Effect of Air Change Rate on Contaminant Removal Performance

Öz

In this study, the effect of air change rate on particle dispersion is investigated experimentally and numerically for different contaminant source positions. An experimental study is carried out on a reduced scale model for isothermal flow conditions and 0.5 µm particles are used as contaminants. Particle motions, based on Lagrange approach, are modeled with a computational fluid dynamics (CFD) software ANSYS Fluent. It is found that pollutants outside the main flow region lead to 12 times higher concentration values. In addition, it is determined that the increase in air change rate decreases the concentration of pollutants in this region by 75%.

Anahtar Kelimeler

• Air change rate (ACH),particle dispersion,contaminant removal

Hava Değişim Katsayısının Kirletici Uzaklaştırma Performansına Etkisinin İncelenmesi

Öz

Bu çalışmada, hava değişim katsayının partikül dağılımına etkisi farklı kirletici kaynak konumları için deneysel ve sayısal olarak incelenmiştir. Deneysel çalışma küçük ölçekli bir model oda üzerinde izotermal akış şartları için yürütülmüş ve kirletici olarak 0,5 µm ebatında partiküller kullanılmıştır. Partikül hareketleri, Lagrange yaklaşımı esas alınarak bir hesaplamalı akışkanlar dinamiği (HAD) yazılımı olan ANSYS Fluent programında modellenmiştir. Ana akış bölgesi dışında yer alan kirleticilerin daha yüksek konsantrasyon değerlerine yol açtığı tespit edilmiştir. Bununla beraber, hava değişim katsayısındaki artışın bu bölgedeki kirletici konsantrasyonunu azaltmada daha etkili olduğu ortaya konmuştur.

Anahtar Kelimeler

• Hava değişim katsayısı (HDK),Partikül dağılımı,Kirletici uzaklaştırma

Kaynakça

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