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The application of synthetic jet in a cross flow has been studied numerically in mostly twodimensional configurations. The synthetic jet is becoming a useful technological tool for flow control. For aerodynamic applications this would be beneficial in reducing fuel consumption by increasing the efficiency of the flow over solid geometries. The present numerical simulation is conducted on a three-dimensional bluff body, a side-supported sphere, in a cross flow. The computational model was constructed based upon the experimental work conducted by the authors [6,16]. The synthetic jet was modelled numerically based upon the harmonic sinusoidal motion of the actuator used in the physical experiments. An open type boundary condition was used in the ANSYS CFX commercial CFD package that has not been previously developed using this software to produce the zero net mass flow condition whilst generating the required velocity profile. The synthetic jet asymmetrical and localised, was located at three different angles of incidence 6.5 o , 76 o and 100 o . The cross flow was set at the Reynolds number of 5 x 10 4 .Since the flow over the side-supported sphere at this Reynolds number is unsteady and the synthetic jet is inherently an oscillating turbulent shear flow it was required to conduct a transient CFD analysis. Two different turbulence models were used to predict separation of the unsteady flow field with the SST turbulence model proving to be most accurate when compared to the experimental data. It was found that the synthetic jet at all angles of incidence improved the surface pressure distribution before separation relative to the baseline case. Post separation the localised synthetic jet increased the crosswise vorticity in the wake region at 6.5 o . With the synthetic jet at 76 o and 100 o produced a similar result by decreasing the size of the wake and streamlining the flow through a breaking up crosswise vorticity in the wake region. Further the interference flow at the support-sphere junction was streamlined leading to a slight decrease in the drag. NomenclatureC p = coefficient of pressure distribution D = diameter of the sphere f = frequency p = static pressure at a point on the sphere p = mean pressure p  = freestream static pressure  q = freestream dynamic pressure Re = Reynolds number t = time u = local streamwise cartesian velocity component u = the RANS mean velocity vector n u = normal velocity vector U max = maximum velocity 2  U = freestream velocity V = local vertical crosswise Cartesian velocity component W = local horizontal crosswise Cartesian velocity component  = absolute viscosity  t = turbulent eddy viscosity  = density  ∞ = freestream desnity  = angular frequency 

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Flows in manifolds is a ubiquitous and important area to implement flow improvements. In almost all applications of industrial pipe flows, there is the requirement to distribute the flow of fluid. There is a deficiency of studies in the area of flow distribution in manifolds with high speed flows. The present work is aimed at providing a further understanding of transient high speed flow distribution in manifolds. The different manifold configurations were analysed computationally. A comparison was focused between through the different aspect ratio manifolds. The velocity field and the eddy viscosity parameters where compared between the simulated flow models to ascertain the key features in the distributed flow field and especially, to determine the areas that showed greater flow recirculation or flow eddies and the separated flow regions. The CFD study was conducted as a high speed flow/ compressible flow regime accounting for the ideal gas dynamic model being air as the working fluid. The study showed that the transient behaviour of flow field can significantly affect distribution of the flow depending on the aspect ratio and number of branches on the manifold. Efficiency gains can be achieved in high speed flows that can be of benefit in industrial and other engineered flow applications.