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INCAS Bulletin 2013
Implementation of a correction factor for the Pohlhausen laminar boundary layer applied on the CEVA curved wall jet modelDOI: 10.13111/2066-8201.2013.5.3.7 Keywords: Coand effect , boundary layer , Pohlhausen method , wall jet , experimental equation Abstract: Curved wall jets have many technical applications, ranging from aeronautical circulation controlled wings to micro-fluidics and cryogenics. This paper addresses the issue of correctly estimating the boundary layer separation for laminar curved wall jets. For this, the Pohlhausen model was used in conjunction with the CEVA wall jet model with a semi-empirical modification which increases the accuracy for very thin jets. The method is therefore a mix of analytical equations with curve fitted experimental data in order to produce a simple yet effective way of estimating the boundary layer velocity profile along the curved wall. In order to cross-check the results, Newman’s empirical equation – which only provides a separation location but no information regarding the velocity profile - for boundary layer separation was used with good results. The hereby model could be used as a pre-design tool for rapid assessment of aeronautical high-lift applications such as Upper Surface Blown (USB) or entrainment wings.
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