CFD Simulation of Exhaust Gas Dispersion into Atmosphere from Industrial Stack

Case Highlights:

Client: Air Pollution Control Systems Manufacturer, USA

The Objective: CFD simulation of exhaust gases emitting from industrial stack, for investigation of SO2 dispersion into atmosphere.


  • Developing wind profile to replicate actual atmospheric conditions at the stack site
  • Developing large atmospheric domain boundaries to capture the exhaust gas dispersion into the atmosphere comprehensively
  • Selecting appropriate turbulence model to obtain meaningful results

Solution: Exhaust gas analysis was performed to investigate the SO2 dispersion in the atmosphere from the industrial stack. A wind profile was developed using UDF (user defined functions) to replicate actual atmospheric conditions. The simulation results showed the dispersion of the SO2 along with other species in to the atmosphere within the 500m radius from the stack.

Simulation of Exhaust Gas Dispersion Simulation of Exhaust Gas Dispersion

Pollutants emitting from the industrial processes are carried away for certain distance from the stack, causing hazardous conditions for the neighboring properties. Pollution control is essential in such cases to avoid adverse effects of the harmful gases on the surrounding community.

Predicting the exhaust gas dispersion allows process industries to tune the machineries and processes to reduce the emission considerably. A leading air pollution control systems manufacturer approached Hi-Tech for a CFD solution to determine SO2 dispersion from the industrial stack.


To replicate the effects of wind on the exhaust gas dispersion, a wind velocity profile was developed using User Defined Function (UDF). The stack domain along with the atmosphere was developed, considering the boundaries of the atmosphere to remain large enough to capture the physics completely.

Considering SO2 content as prime among the other species, the exhaust gas analysis was performed using CFD to measure the SO2 distribution into the atmosphere. The results showed that the SO2 dispersion at around 500m was less than 10PPMV.


  • Identified the dispersion of SO2 in terms of mass and volume fraction
  • Predictions of exhaust gas dispersion suggested process plant designer to modify the equipment design accordingly
  • The amount of SO2 concentration above the specified distance was found within nominal range

About Hi-Tech

Hi-Tech CFD is a division of Hi-Tech Outsourcing Services, a pioneer engineering outsourcing company since 1992 based in India & USA. It provides expert Computer Aided Engineering - CAE consulting services for engineering / product design analysis by modeling & simulation.

The primary services extended include Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA), product design optimization and value engineering services to Automotive, Building / Construction, Process industry, Power Generation, Manufacturing & Heavy Engineering industries.

Our Clients
  • Addject
  • Bruce
  • CCI
  • Claymore-Home
  • Cleanteq
  • Crosstown
  • Densitron
  • Emerson
  • GSI
  • Innovida
  • Jacobs
  • Larson
  • MITChell
  • Nomenca
  • Siemens
  • MIT
  • Xaloy