searching for "Submerged Duct" displaying records 1 - 6 of a total of 6 1. An experimental investigation of the design variables for NACA Emmet A. Mossman , Lauros M. Randall , NACA Ames Aeronautical Laboratory (Moffett Field, Ca, United States) NACA RM-A7I30, , 1948 Information concerning the parameters and design variables affecting an NACA submerged duct design is presented. The principal variables investigated include entrance width-to-depth ratio, ramp-wall divergence, ramp angle, and deflector size. Tests were also made to show the effect of variation of boundary-layer thickness and ramp-floor contour. Pressure recovery at the duct entrance and after slight diffusion, pressure distribution over the lip and ramp, and drag are given as functions of the inlet velocity ratio of the entrance. An evaluation of the NACA submerged entries indicates that satisfactory duct characteristics may be found for a range of the test variables. It appears that an optimum NACA submerged inlet design should employ curved diverging ramp walls, a 5 degree to 7 degree ramp angle, and a width-to-depth ratio of from 3 to 5. The boundary-layer thickness of the surface into which the inlet is placed was found to have a large effect on the pressure recovery. Possible applications of this types of inlet and their particular advantages are discussed. http://naca.larc.nasa.gov/reports/1948/naca-rm-a7i30/ Updated/Added to NTRS: 2003-08-19 2. An investigation of submerged air inlets on a 1/4-scale model of a typical fighter-type airplane Delany, Noel K. , Ames Aeronautical Laboratory, Moffett Field, Calif. NACA Research Memorandum A8A20, 48 pp. , 1948 Wind-tunnel tests were made of submerged air inlets on the fuselage of a 1/4-scale model of a typical fighter-type airplane. The results are presented for ramp plan forms with parallel and diverging walls, and show the effects on the ram recovery ratio and predicted critical Mach number of the duct entrance location (forward of the wing and over the wing), internal ducting efficiency, angle of attack, and the use of deflectors. Drag increments of the inlets are presented for the forward location. http://naca.larc.nasa.gov/reports/1948/naca-rm-a8a20/ Updated/Added to NTRS: 2003-08-19 3. Tests of submerged duct installation on a modified airplane in the Ames 40- by 80-foot wind tunnel Martin, Norman J , NACA Ames Aeronautical Laboratory (Moffett Field, Calif., United States) NACA RM-A7I29, 25 pp. , 1947 No Abstract Available http://naca.larc.nasa.gov/reports/1947/naca-rm-a7i29/ Updated/Added to NTRS: 2003-08-19 4. Development of NACA submerged inlets and a comparison with wing leading-edge inlets for a 1/4-scale model of a fighter airplane Mossman, Emmet A. , Gault, Donald E. , Ames Aeronautical Laboratory, Moffett Field, Calif. NACA Research Memorandum A7A31, 44 pp. , 1947 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. http://naca.larc.nasa.gov/reports/1947/naca-rm-a7a31/ Updated/Added to NTRS: 2003-08-19 5. Tests of submerged duct installation on the Ryan FR-1 airplane in the Ames 40- by 80-foot wind tunnel /y Norman J. Martin Martin, Norman J. , Ames Aeronautical Lab., Moffett Field, CA NACA Research Memorandum A7D14, 27 pp. , 1947 An investigation of an NACA submerged intake installation on the Ryan FR-1 was conducted to determine the full-scale aerodynamic characteristics of this installation. In addition, tests were conducted on the submerged inlet with revised entrance lips and deflectors to determine the configuration which would result in the best dynamic pressure recovery measured at the inlet for this installation without a major rework of the entrance. Stalling of the air flow over the inner lip surface created excessive dynamic pressure losses with the original entrance. The revised entrance produced a 12-percent increase in dynamic pressure recovery at the design high-speed inlet-velocity ratio and resulted in an improvement of the critical-speed characteristics of the entrance lip. A complete redesign of the entrance including a decrease in ramp angle and adjustment of lip camber is necessary to secure optimum results from this submerged duct installation. http://naca.larc.nasa.gov/reports/1947/naca-rm-a7d14/ Updated/Added to NTRS: 2003-08-19 6. An Experimental Investigation of NACA Submerged-Duct Entrances Charles W. Frick , Wallace F. Davis , Lauros M. Randall , Emmet A. Mossman , Ames Aeronautical Laboratory, Moffett Field, CA NACA ACR-5I20, , 1945 The results of a preliminary investigation of submerged-duct entrances are presented. It is shown that an entrance of this type posses desirable critical speed and pressure recovery characteristics when used on a fuselage or nacelle in a region of low incremental velocity and thin boundary layer. The data obtained indicate that submerged entrances are most suitable for use with internal-flow system which diffuse the air only a small amount: for example, those used with jet motors which have axial-flow compressors. When complete diffusion of the air is required, fuselage-nose or wing leading-edge inlets may prove to be superior. The results of the investigation have been prepared in such a form as to permit their use by a designer and the application of these data to a specified design is discussed. http://naca.larc.nasa.gov/reports/1945/naca-acr-5i20 Updated/Added to NTRS: 2003-08-19 searching for "Submerged Duct" displaying records 1 - 6 of a total of 6 Sponsored by the NASA Scientific and Technical Information Program Office Responsible NASA Official: Calvin E. Mackey; Curator: ConITS Development Team Viewers: Adobe Acrobat (PDF), PostScript, MS Office, Compression Privacy & Copyright, Ordering NASA Information, NASA STI Help Desk Last Updated: Mon Apr 12 12:00:00 EDT 2004