An extended model for orifice starting jets

Starting jets emanating from a straight nozzle and orifices of different orifice-to-tube diameter ratios are investigated using time-resolved particle image velocimetry. The invariants the motion, namely, circulation, hydrodynamic impulse, kinetic energy, measured compared to classic slug-flow model, this for both fixed exhaust speed diameter-based Reynolds numbers. An extension model is proposed account contraction fluid experiencing when being pushed out through orifice geometries. coefficients obtained two-dimensional formed slit in channel applied axisymmetric problem. This modified shown better predict motion with discrepancies order 10% underpredictions 130%, 50%, 120% respectively, model. Moreover, target speed, suggests existence maximum production impulse energy at an ratio about 0.9, which was also observed experimentally energy. Practically speaking, that most efficient way producing starting jet plate close 1, but nozzle. Finally, overpressure correction Krueger [“The significance vortex ring formation exit pulsatile propulsion,” Ph.D. thesis (California Institute Technology, 2001)] revisited ratio. Overall, good agreement present experimental data found.