A multidimensional model for transient sprays and gas jets is employed to study entrainment characteristics in the near field of a gas jet. Turbulence is represented using a k-e model. Local entrainment and mass flux in the near field of the jets were estimated as functions of axial distance from the jet orifice. Integrated radial mass inflow to the center of the jet as a function of radial distance was also examined. The results are compared with published trends in the literature. The behavior of the entrainment constant is also examined in the near field. The effect of the near field entrainment characteristics on the far field behavior of the jet is discussed. The influence of the orifice velocity profile on entrainment characteristics is also discussed. Computed results of centerline velocity in steady gas jet are compared to particle image velocimetry measurements made in gas jets. The implications of these results for modeling transient jets in engines are critically evaluated.
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