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The focus of the present article is to study the effect of liquid jet injection velocity profile on the structure of liquid jet in crossflow(JICF).The experiments are conducted over a range of liquid-to-air momentum ratios(Q~3-100)and aerodynamic Weber numbers(We = 17 – 89).Control over the velocity profile of the injected liquid is achieved through the usage of different L/d ratios of the nozzle of the plain-orifice atomizer.The geometrical parameter L/d is varied between 10 and 100 in order to obtain fully-developed laminar flow at the shortest end and turbulent flow at the longest end,with the transition from laminar to turbulent flow happening in between.Laser Diagnostics and high-speed imaging techniques are used to study the trajectory,drop-sizing and transient behavior of the resultant spray.It is then observed that the dependence of trajectory of the spray is not just limited to the well-accepted parameter – Q,but also requires correction factors with respect to the injection velocity profiles which are in turn related to the L/d numbers in the current study.The trajectory for turbulent jet is found to be lower at all times when compared to that of a laminar jet for corresponding conditions.This behavior may be attributed to the inherent instabilities present in a turbulent jet as opposed to a perfectly smooth laminar jet.An attempt has also been made to investigate the transient phenomena of the liquid jet breakup at different conditions with the aid of Proper Orthogonal Decomposition(POD)analysis.Distinct modes of breakup are captured for the laminar and turbulent cases.Thus,the present investigation emphasizes the importance of boundary conditions for JICF studies.