EXPERIMENTAL-STUDY ON MIXING ENHANCEMENT BY PETAL NOZZLE IN SUPERSONIC-FLOW

An experimental study on mixing enhancement in supersonic flow by a ra dially lobed nozzle, called petal nozzle, has been conducted, The stud y entails the mixing of a supersonic primary stream and a coflowing so nic secondary stream in cold now, The radial distribution of momentum flux is characterized by a mixing parameter called the degree of mixin g, The loss in stagnation pressure associated with the mixing is also determined. With emphasis on momentum mixing and pressure drop, the pe tal nozzle and the conventional conical nozzle have been compared so a s to assess the suitability of the former, The results show that using an optimum length of the mixing chamber, a compromise can be struck b etween the mixing enhancement and the associated increase in pressure loss. The contribution of shear area at the nozzle exit to mixing enha ncement was found to be marginal.