title: Numerical study of a buoyant plume from a multi-flue stack into a variable temperature gradient atmosphere.
abstract: Air pollution is one of the major global hazards and industries have been one of its major contributors. This paper primarily focuses on analyzing the dispersion characteristics of buoyant plumes of the pollutant released from a multi-flue vertical stack into a variable temperature gradient atmosphere (α) in a constant-velocity cross wind using two stack configurations-inline and parallel. The study is conducted for different Froude numbers, Fr = 12.64, 9.55, and 8.27. The atmospheric temperature gradients considered for the study are 0, +1, +1.5, and +2 K/100 m. The numerical study is done using the commercial computational fluid dynamics (CFD) code FLUENT. The effects of stack configuration, α, and Fr on the plume characteristics are presented. It is observed that the plume rises higher and disperses over a larger area with the inline configuration due to better mixing and shielding effect. With higher α, it is seen that the plume rises initially and then descends due to variation of the buoyant force. The plume rise initially is strongly influenced by the momentum of the jet, and as it moves downstream, it is influenced by the cooling rate of the plume. Furthermore, the plume rises higher and disperses over a larger area with a decrease in Fr.
authors.affiliation: Department of Mechanical Engineering, Ettimadai Campus, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India. ratnavk@gmail.com.
authors.forename: Ratna Kishore
authors.initials: RK
authors.lastname: Velamati
authors.affiliation: Department of Mechanical Engineering, Ettimadai Campus, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Vivek
authors.affiliation: Department of Mechanical Engineering, Ettimadai Campus, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India.
authors.forename: K
authors.initials: K
authors.lastname: Goutham
authors.affiliation: Department of Mechanical Engineering, Ettimadai Campus, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India.
authors.forename: G R
authors.initials: GR
authors.lastname: Sreekanth
authors.affiliation: Department of Mechanical Engineering, Ettimadai Campus, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India.
authors.forename: Santosh
authors.initials: S
authors.lastname: Dharmarajan
authors.affiliation: Centre for Environmental Engineering, PRIST University, Vallam, Thanjavur, India.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Goel
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry*; D001272:Atmosphere / Q000737:chemistry*; D008962:Models, Theoretical; D013696:Temperature; D014919:Wind
chemical_list: D000393:Air Pollutants
keywords: Atmospheric temperature gradient; Buoyant plumes; Froude number; Multi-flue stack; Plume dispersion