Download or read book Evaluation of the Twin Nozzle afterbody Drag and Nozzle Internal Performance Computer Deck with ESIT Free Jet Data written by Phillip C. Everling and published by . This book was released on 1974 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Jet Velocity and Axial Location of Nozzle Exit on the Performance of a Twin jet Afterbody Model at Mach Numbers Up to 2 2 written by Bobbly Lee Berrier and published by . This book was released on 1969 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integrated Airframe Nozzle Performance for Designing Twin engine Fighters written by Edsel R. Glasgow and published by . This book was released on 1973 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Analytical Determination of Integrated Airframe Nozzle Performance written by Edsel R. Glasgow and published by . This book was released on 1972 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: A computer program has been developed for predicting twin-nozzle/aftbody drag and internal nozzle performance for fighter type aircraft having twin buried engines and dual nozzles. The program is capable of generating the installed thrust-minus-drag data required for conducting mission analysis studies of aircraft of this type. The configuration variables which can be analyzed include (1) nozzle type (convergent flap and iris, convergent-divergent with and without secondary flow, and shrouded and unshrouded plug), (2) nozzle lateral spacing, (3) interfairing type (horizontal and vertical wedge), (4) interfairing length, and (5) vertical stabilizer type (single and twin). The performance prediction methods incorporated in the program are based almost entirely on empirical correlations. Specifically, correlations used in conjunction with one-dimensional flow relationships are employed for the prediction of the nozzle thrust and discharge coefficients, and correlations of the test data obtained during the contracted effort are employed for prediction of the aft-end drag. The prediction methods account for the effects of nozzle pressure ratio and flow separation on both internal and external nozzle surfaces. This manual describes the operation of the computer program in terms of program input requirements, performance prediction methods, and output format and includes a presentation of sample input/output cases and a complete computer listing of the program. The program has been developed for use on the CDC 6600 computer.
Download or read book Exhaust Plume Temperature Effects on Nozzle Afterbody Performance Over the Transonic Mach Number Range written by C. E. Robinson and published by . This book was released on 1974 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of an experimental and analytical research investigation on nozzle/afterbody drag are presented. Experimental afterbody (and boattail) drag coefficients and pressure distributions are discussed for an isolated, strut-mounted nozzle/afterbody model for the Mach number range from 0.6 to 1.5. Some data are also given for free-stream unit Reynolds numbers from one million to approximately four million per foot. The experimental data were obtained for the basic model with an air-cooled and a water-cooled Ethylene/air combustor to provide hot-jet duplication as well as cold-jet simulation. The temperature of the nozzle exhaust gas was varied from 530R (burner-off) to approximately 2500R for several nozzle pressure ratios from jet-off to those corresponding to a moderately under-expanded exhaust plum. The initial series of experiments was conducted with the air-cooled combustors, and the effect of jet temperature on afterbody drag was somewhat masked by the effects of the secondary airflow from the cooling air. The general trend, however, shows a decreasing afterbody drag with increasing exhaust gas temperature and with decreasing secondary airflow at a fixed nozzle pressure ratio. (Modified author abstract).
Download or read book An Evaluation of Jet Simulation Parameters for Nozzle Afterbody Testing at Transonic Mach Numbers written by William Lee Peters and published by . This book was released on 1976 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to evaluate various jet simulation parameters in an attempt to establish a method of matching hot jet interference with cold jet flows. Successful parameters were determined based on their ability to correlate integrated afterbody pressure drag, a measurement of aerodynamic interference, for jet flows of varying total temperature. Data used in this investigation were obtained from experiments conducted in the AEDC Propulsion Wind Tunnel (16T) with three different isolated nozzle/afterbody configurations at free-stream Mach numbers from 0.6 to 1.5. Gas temperature effects on pressure drag were acquired with a convergent nozzle utilizing an air/ethylene burner to produce gas temperatures from 540 to 3,300 R. In addition, the jet effects of varying internal nozzle geometry, specifically nozzle divergence half-angle and nozzle exit-to-throat area ratio, were investigated utilizing high-pressure air as the nozzle exhaust gas. Jet simulation parameters were evaluated for jet flows where nozzle exit-to-throat area ratio was varied from 1.0 to approximately 1.5 and where divergence half-angle was varied from 0 to 10 deg.
Download or read book An Evaluation of Nozzle Afterbody Code written by Frederick C. Guyton and published by . This book was released on 1986 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Data Base for the Prediction of Airframe propulsion System Interference Effects written by and published by . This book was released on 1979 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Afterbody Drag Investigation of a Twin nozzle Fighter type Model at Mach Numbers from 0 6 to 1 5 written by Earl A. Price (Jr.) and published by . This book was released on 1972 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Method for Correcting Nozzle Afterbody Drag for the Effects of Jet Temperature written by W. L. Peters and published by . This book was released on 1981 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to isolate those parameters defined as jet mixing effects on afterbody drag in an effort to develop a method of correcting or simulating the effects of jet temperature in wind tunnel experiments. Data used in the investigation were obtained from experiments conducted in the AEDC Aerodynamic Wind Tunnel (1T) with a strut-mounted model at free-stream Mach numbers from 0.6 to 1.2. Integrated afterbody pressure drag coefficient data were acquired for three nozzle area ratios (1.0, 1.24, and 2.96) using various unheated jet exhaust gas compositions that allowed a variation in gas constant from 55 to 767 ft/lbf/lbm-deg R. Jet mixing effects on afterbody drag coefficient produced by varying jet gas constant and nozzle area ratio at nozzle design pressure ratio, and the drag effects resulting from variations in nozzle pressure ratio at certain overexpanded jet conditions were observed to be similar functions of mass flux ratio. A simple experimental method has been proposed to allow corrections of afterbody drag coefficient data obtained in the wind tunnel (using an ambient temperature air jet) for the effects of jet gas constant. By inference, a similar drag correction can be obtained for the combined effect of gas constant and temperature, assuming their product defines the effects on drag produced by variations in either property. (Author).
Download or read book Experimental and Analytical Determination of Integrated Airframe Nozzle Performance Volume II Operating Manual for Twin Nozzle Aftbody Drag and Internal Nozzle Performance Computer Deck written by Edsel R. Glasgow and published by . This book was released on 1972 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: A computer program has been developed for predicting twin-nozzle/aftbody drag and internal nozzle performance for fighter type aircraft having twin buried engines and dual nozzles. The program is capable of generating the installed thrust-minus-drag data required for conducting mission analysis studies of aircraft of this type. The configuration variables which can be analyzed include (1) nozzle type (convergent flap and iris, convergent-divergent with and without secondary flow, and shrouded and unshrouded plug), (2) nozzle lateral spacing, (3) interfairing type (horizontal and vertical wedge), (4) interfairing length, and (5) vertical stabilizer type (single and twin). The performance prediction methods incorporated in the program are based almost entirely on empirical correlations. Specifically, correlations used in conjunction with one-dimensional flow relationships are employed for the prediction of the nozzle thrust and discharge coefficients, and correlations of the test data obtained during the contracted effort are employed for prediction of the aft-end drag. The prediction methods account for the effects of nozzle pressure ratio and flow separation on both internal and external nozzle surfaces. This manual describes the operation of the computer program in terms of program input requirements, performance prediction methods, and output format and includes a presentation of sample input/output cases and a complete computer listing of the program. The program has been developed for use on the CDC 6600 computer. (Author).
Download or read book An Evaluation of Jet Simulation Parameters for Nozzle Afterbody Testing at Transonic Mach Numbers written by and published by . This book was released on 1976 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to evaluate various jet simulation parameters in an attempt to establish a method of matching hot jet interference with cold jet flows. Successful parameters were determined based on their ability to correlate integrated afterbody pressure drag, a measurement of aerodynamic interference, for jet flows of varying total temperature. Data used in this investigation were obtained from experiments conducted in the AEDC Propulsion Wind Tunnel (16T) with three different isolated nozzle/afterbody configurations at free-stream Mach numbers from 0.6 to 1.5. Gas temperature effects on pressure drag were acquired with a convergent nozzle utilizing an air/ethylene burner to produce gas temperatures from 540 to 3,300 R. In addition, the jet effects of varying internal nozzle geometry, specifically nozzle divergence half-angle and nozzle exit-to-throat area ratio, were investigated utilizing high-pressure air as the nozzle exhaust gas. Jet simulation parameters were evaluated for jet flows where nozzle exit-to-throat area ratio was varied from 1.0 to approximately 1.5 and where divergence half-angle was varied from 0 to 10 deg.
Download or read book Effect of Nozzle Lateral Spacing on Afterbody Drag and Performance of Twin jet Afterbody Models with Convergent Nozzles at Mach Numbers Up to 2 2 written by Donald L. Maiden and published by . This book was released on 1970 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Analytical Determination of Integrated Airframe Nozzle Performance written by Edsel R. Glasgow and published by . This book was released on 1972 with total page 714 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental and analytical investigation of the installed thrust and drag of various isolated nozzle and twin-nozzle/aftbody configurations indicated that empirical correlations provide the best means of predicting aft- end performance, especially for the early stages of the aircraft design. Both subsonic and transonic isolated nozzle drag data were correlated using IMS (integral mean slope) as the geometric parameter. A correlation of twin-nozzle/aftbody drag data at subsonic and transonic speeds was developed by combining Spreiter's transonic similarity parameters with the IMS of the equivalent body of revolution. A correlation of inviscid MOC pressure drag, achieved through use of IMS combined with similarity parameters obtained from linearized supersonic flow theory, provided an accurate and rapid means of estimating drag for arbitrary axisymmetric boattail contours at supersonic speeds. Twin-nozzle/aftbody drag data at supersonic speeds was correlated with the equivalent body drag obtained from the axisymmetric MOC correlation. Improved thrust and drag performance was obtained by modifying the aft-end design of five selected aircraft configurations. The rationale for these modifications was derived from design guidelines and criteria developed during the program. Improvements in mission radius for a fixed takeoff gross weight aircraft were obtained, in general, by utilizing convergent-divergent nozzles, a horizontal wedge interfairing with the trailing edge terminating at the exit plane of the nozzles, a single vertical stabilizer, and a narrow lateral nozzle spacing.
Download or read book A Method for Estimating Jet Entrainment Effects on Nozzle afterbody Drag written by R. C. Bauer and published by . This book was released on 1980 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: A highly simplified analysis was used to derive an expression for estimating the induced afterbody drag caused by the turbulent jet-mixing process. The approach estimates the induced velocity produced by the jet-mixing process and uses small perturbation concepts to estimate the resulting pressure change on the afterbody surface from which the induced afterbody drag coefficient is obtained. The theoretical induced afterbody drag (entrainment drag) is combined with the maximum jet plume diameter blockage condition to form a correlation method that accounts for the effect of jet area ratio, exit angle, total temperature, molecular weight and ratio of specific heats for a given external stream Mach number, Reynolds number, and afterbody geometry. For verification, the correlation method was used to predict the drag of an H2 and C2H4 jet from the measured drag of an N2 jet and to predict the drag of a hot jet from the measured drag of a cold jet for both the 15- and 25-deg AGARD afterbody configurations in the Mach number range from 0.6 to 1.5. The average accuracy of the correlation method is better than 10% for both afterbody configurations and is 40 to 50 % more accurate than a correlation method based only on the blockage parameter. A brief numerical study indicates that the major parameter which correlates the jet entrainment effect is the product of the jet gas constant and total temperature. (Author).
Download or read book Evaluation of Reynolds Number and Tunnel Wall Porosity Effects on Nozzle Afterbody Drag at Transonic Mach Numbers written by C. E. Robinson and published by . This book was released on 1976 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation was conducted to study the effects of Reynolds number variation on isolated nozzle afterbody performance. A strut-mounted cone-cylinder model with three separate afterbody configurations for Aerospace Research and Development (AGARD) was used for this investigation. This program was conducted in two phases distinguished by the model size and the wind tunnels used to obtain the experimental results. The effect of tunnel wall porosity on nozzle afterbody (NAB) performance was investigated.
Download or read book Effect of Nozzle Lateral Spacing on Afterbody Drag and Performance of Twin jet Afterbody Models with Convergent divergent Nozzles at Mach Numbers Up to 2 2 written by Odis C. Jr Pendergraft and published by . This book was released on 1972 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:
