The primary aim of the present experimental study is to describe the pertinent characteristics of flow, temperature and concentration field in the non-premixed jet with and without flame in a cross air flow. We demonstrated the details of the various vortex structures with low jet and cross flow velocities. The data presented on the distribution of the mean scalar quantities also should be of interest and value to whom concerned in numerical prediction of 3-D reacting and non reacting flow.
The effects of cross flow and jet velocities on flame trajectory were examined to investigate the behavior of jet flame. It appears that the flame trajectory is significantly influenced by the magnitude of initial momentum and flame buoyance. From the value of gradient of flame trajectory, we can define two regions of flow as a momentum-dominant region at near nozzle and a buoyance-dominant region far downstream. The boundary of these regions is the position where the value of the gradient of flame trajectory is minimum. The critical length was found to be increased as the jet velocity is increased or the cross flow velocity is increased.
In order to know the detailed flow structure inside flame front we employed RMS (Reactive Mie Scattering) technique and put our attention on the inner vortices inside jet flame in cross flow. The organized inner vortices inside the luminous flame at low jet velocity with cross air flow are observed. The location of them also change from lee side to windward side with increase of the jet velocity. It is evident that two vortex systems are responsible for the flow behavior in this flow field.
Temperature near nozzle field is maximum at the upper edge, but when flame is developed downstream, the position of maximum temperature moves to lower edge. It is due to development of bound vortex which exists at the lee side.
