Scaling of Vorticity Flux and Entrance Length Effects in Zero-Net Mass-Flux Devices
نویسندگان
چکیده
Two-dimensional numerical simulations are used to examine the vorticity flux and slot entrance effects in zero-net mass-flux devices. The simulations allow us to extract a simple scaling law for the vorticity flux which provides insight into the relative importance of the various operational parameters. In addition to this, a semi-analytical model is proposed in order to determine the pressure loss across an orifice or slot for oscillatory flows. A key parameter in this model is the normalized entrance length and numerical simulations are used to determine the variation of this parameter with the jet Strouhal number.
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