Enhancement of mixing in reacting fuel-rich plumes issued from elliptical nozzles

The mixing of jets and reacting fuel-rich plumes issued from elliptical and circular nozzles was compared in the tests reported in this paper. In noiireactirig tests with hotwire probes, the jet issued from an elliptical nozzle mixed faster with a coaxial, ducted airstream than a jet issued from a circular nozzle. In combustion tests with thermocouples, mixing between the reacting fuel-rich plume and the coaxial air was also enhanced with elliptical nozzles. This resulted in higher local combustion temperatures and therefore higher reaction rates near the nozzle exit. In both cases, the tests were done at high Reynolds numbers and turbulent initial conditions.