In ground test applications for simulated embedded engine systems, it is often necessary to forego direct-connect inlet/engine configurations and simulate inlet produced distortion profiles. Classically, this has been accomplished through the use of wire-mesh screens layered over a thick supporting grid. Other traditional approaches of distortion generation rely on active controls and/or empirical loss models for various geometries (such as airfoils, cylinders, and screens). These widely tabulated loss models limit the design of such device elements to those available in the literature. The freedom provided by advanced manufacturing methods would significantly expand the design space for such an application, giving rise to complex geometries that are not commercially available or feasible to manufacture. Therefore, an accurate distortion model relating total pressure losses to any geometry is necessary for a true design optimization of the distortion generator. This paper presents such a model by relating total pressure losses to various system interactions in classical fluid dynamic relationships. The total pressure loss models are formulated for incompressible and compressible flow conditions, where the total pressure across the screen is manipulated by either a mass exchange or adjusting the drag characteristics of the screen. This model is fully derived for the case of incompressible flow with drag, and validated against experimental data collected from a low-speed wind tunnel test. The accurate prediction of the reduced-order model with the low-speed results gives rise to a higher fidelity "continuous" screen in which every cell is tailored for a specific total pressure value.
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