An Innovative Wind Tunnel for Evaluating Gaseous Emissions from Agricultural Land or Liquid Surfaces

Wind tunnels are widely used for comparing gaseous emissions from different treatments as well as for simulating emissions as affected by different environmental parameters. However, current wind tunnels pull air over the treated surface using axial fans that create wind speed profiles that show declining speed with height whereas in nature, wind speed increases with height over a flat, level surface. This paper describes the development of a proof-of-concept wind tunnel powered by two 12-V batteries. It was tested in the lab at nominal wind velocities ranging from 0.3 to 1.5 m/s using a loop-pile carpet as the 'rough' surface. In the 1-m long test section, where velocity profiles did not change either with velocity or distance, wind velocity increased logarithmically with height (20-80 mm), as would be observed under neutral conditions over a flat and smooth surface. This wind tunnel can be used for low wind speed testing. Velocity values across the width of the wind tunnel were similar. Additional evaluation is required.