Entrainment characteristics of transient gas jets

Results are presented of theoretical analysis and computations of transient gas jets in a quiescent ambient environment, with injected to ambient density ratios of 2, 1, and 0.5. Comparisons of these results with those from previous work in gas jets are also presented. Turbulence is represented using a k-epsilon model. Entrainment rate is found to scale linearly with axial penetration, and the total mass entrained is shown to have a cubic dependence on axial penetration of the gas jet. The actual values of these quantities depend on a constant whose value obtained from measurements and quoted in the literature varies by as much as a factor of 2.