An experimental investigation of the design variables for NACA submerged duct entrances

Information concerning the parameters and design variables affecting an NACA submerged duct design is presented

Development of NACA Submerged Inlets and a Comparison with Wing Leading-Edge Inlets for a 1/4-scale Model of a Fighter Airplane

Characteristics of NACA submerged duct entries and wing leading-edge inlets designed for a 1/4 scale flow model of a fighter-type airplane powered by a jet engine in the fuselage are presented

An Experimental Investigation of NACA Submerged-Duct Entrances

The results of an investigation of submerged-duct entrances are presented. It is shown that this type of entrance possesses the following characteristics: 1) very high-critical-compressibility speeds throughout the range of high-speed inlet velocity ratios; 2) very low pressure losses for the air entering the duct at all inlet-velocity ratios; and, 3) low external drag. These characteristics are obtained by the proper shaping of the contour of the upstream approach to the submerged inlets and by proper alignment of the duct lip. Design data are presented and the application of these data to a specific high-speed fighter-airplane design is discussed