Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
An Experimental Investigation Of Two Dimensional Thrust Augmenting Ejectors
Download An Experimental Investigation Of Two Dimensional Thrust Augmenting Ejectors full books in PDF, epub, and Kindle. Read online An Experimental Investigation Of Two Dimensional Thrust Augmenting Ejectors ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis An Experimental Investigation of Two-Dimensional Thrust Augmenting Ejectors by : L. Bernal
Download or read book An Experimental Investigation of Two-Dimensional Thrust Augmenting Ejectors written by L. Bernal and published by . This book was released on 1984 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments were performed with subsonic and underexpanded choked two-dimensional primary nozzle ejector flow systems without diffusion to evaluate the role of entrainment and mixing in thrust augmentation. Two-component Laser Doppler velocity measurements (mean and fluctuating values), thrust measurements, ejector shroud surface pressure measurements and flow visualization were used to determine the evolution of the velocity profiles and their relationship to the ejector performance. Key findings include: (1) Primary jet growth is significantly altered by the ejector shroud. (2) Primary jet turbulent characteristics when normalized with the local mean centerline velocity are in agreement with those for the free-jet. (3) In the neighborhood of the ejector shroud the flow field can be classified into two regions--the potential flow region and the region close to the ejector exit which is dominated by the turbulent transport. (4) Pressure recovery is very sharp in the first region and is more gradual in the region close to the ejector exit. The investigation is continuing toward the near-term objectives of obtaining measurements within diffused flow and with heated primary air. This volume emphasizes the laser doppler velocimetry developed especially for this program. Part II (AD-A154 083) presents detailed cold flow measurements along with preliminary primary hot flow data.
Book Synopsis An Experimental Investigation of Two-Dimensional Thrust Augmenting Ejectors by : L. Bernal
Download or read book An Experimental Investigation of Two-Dimensional Thrust Augmenting Ejectors written by L. Bernal and published by . This book was released on 1984 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow-field within a two-dimensional thrust augmenting ejector has been documented experimentally. Results are presented on the mean velocity field and the turbulent correlations by laser doppler velocimeter, surface pressure distribution, surface temperature distribution, and thrust performance for two shroud geometries. The maximum primary nozzle pressure ratio tested was 3.0. The tests were conducted at primary nozzle temperature ratios of 1.0, 1.8, and 2.7. Two ejector characteristics lengths were identified based on the dynamics of the ejector flow field--a minimum length below which no significant mixing occurs, and a critical length associated with the development of U'V' correlation in the ejector. These characteristic lengths divide the ejector flow field into three distinctive regions: the entrance region where there is no direct interaction between the primary flow and the ejector shroud; the interaction region where there is an increased momentum of induced flow near the shroud surface; and a 'pipe' flow region characterized by an increased skin friction. The effect of the coflowing induced flow shown to produce inside the ejector a centerline velocity that increased over the free-jet data. The normalized turbulent correlations are found to be 25% lower than those in free jets. Effects of pressure ratio on the ejector flow field are small. Present measurements also show that the ejector performance was not influenced by the primary nozzle temperature ratio up to 2.7.
Book Synopsis Experimental Investigation of a Thrust Augmenting Ejector by : Hidayat Wiradimadja
Download or read book Experimental Investigation of a Thrust Augmenting Ejector written by Hidayat Wiradimadja and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An ejector is basically a jet pump in which the kinetic energy of the jet is made to impart motion to the fluid surrounding it. During this process, in a well design system, the ejector as a whole experiences a thrust much higher than that of the jet alone. In principle, an ejector is nothing but a jet surrounded by a shroud. This investigation concerns the performance of a two- dimensional ejector with its primary jet excited by a novel method. A constant area duct was used in this experiment. The velocity of the jet at the exit was subsonic. Maximum thrust was obtained when the ejector to jet exit area ratio was about 35. Under this condition a thrust augmentation ratio of 1.65 was achieved, with the jet excited at 20 Hz, whereas without excitation it was only 1.40. The mixing characteristics of the jet under excitation was examined using flow visualization techniques. Smoke filaments illuminated by a sheet of powerful light and schlieren optics with the jet heated were used. Excitation of the jet was found to generate large vortex-like flow structures which might be responsible for enhanced mixing. These vortices extended to considerable distances on both sides of the jet.
Book Synopsis Workshop on Thrust Augmenting Ejectors by :
Download or read book Workshop on Thrust Augmenting Ejectors written by and published by . This book was released on 1979 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental Investigation of Thrust Augmenting Ejector Flows by : L. Bernal
Download or read book Experimental Investigation of Thrust Augmenting Ejector Flows written by L. Bernal and published by . This book was released on 1982 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of two investigations, one recently completed on pulsatile ejector flows and the second currently in progress on a two-dimensional ejector configuration are presented. The objective of these investigations is to determine the role of entrained fluid and its mixing with the primary jet on ejector performance. Results will also be presented on the effects of entrance geometry on ejector entrainment and thrust augmentation.
Book Synopsis Experimental Investigation of Thrust Augmenting Ejectors Using Vane Excited Primary Jets by :
Download or read book Experimental Investigation of Thrust Augmenting Ejectors Using Vane Excited Primary Jets written by and published by . This book was released on 1982 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation has been conducted to evaluate the entrainment characteristics of a thrust augmenting ejector, with a small, oscillating airfoil inserted in the potential core of the primary jet. Velocity distributions were measured across the width of the jet, at downstream distances of 20 and 40 nozzle widths, with the jet exhausting into still air and with the jet exhausting into an instrumented ejector shroud for the following range of parameters: Pressure ratio 1.137 and 1.268, amplitude of oscillation 2.6 deg and 6.9 deg zero-to-peak frequency of oscillation 0, 20, 40 and 60 Hz. Static pressure distributions were measured within the shroud when the jector was installed. The results amplify previously conducted studies. Jet spreading and entrainment appear to increase with increasing amplitude and frequency of oscillation and to decrease with increasing nozzle pressure ratio. (Author).
Book Synopsis An Experimental Study of a Three-dimensional Thrust Augmenting Ejector Using Laser Doppler Velocimetry by : Bruce Lowell Storms
Download or read book An Experimental Study of a Three-dimensional Thrust Augmenting Ejector Using Laser Doppler Velocimetry written by Bruce Lowell Storms and published by . This book was released on 1989 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental Investigation of High Performance, Short, Thrust Augmenting Ejectors by :
Download or read book Experimental Investigation of High Performance, Short, Thrust Augmenting Ejectors written by and published by . This book was released on 1983 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of an experimental investigation concerning the design and testing of air-to-air thrust augmenting ejectors utilizing short curved-wall diffusers are presented. These ejectors were designed primarily according to the procedure established in an analytical research effort sponsored by DTNSRDC from 1980-1981. Two of the three ejectors tested have identical mixing chambers. The mixing chamber inlet area to the primary nozzle area ratio lambda was 40. The overall ejector length-to-mixing chamber diameter ratios L/D(overall) were 6.09 and 6.16; diffuser area ratios AR(diff) were 1.33 and 1.46, respectively. The third ejector had an L/D(overall) of 6.02, a lambda of 20 and an AR(diff) of 1. 26. The best observed thrust augmentation ratio phi and the modified thrust augmentation ratio phi sub 2 were 2.11 and 1.91 respectively for a sonic primary jet. The modified thrust augmentation ratio phi sub 2 accounts for the penalty of suction in preventing flow separation in the diffuser. These levels of thrust ratio were derived from velocity measurements at the ejector exit. Independent thrust measurements obtained with strain gages on the mixing chamber agree with the force calculated from the momentum data. The experimentally observed ejector performance data correlated well with the predicted values. (Author).
Book Synopsis Experimental Investigation of Thrust Augmenting Ejectors Using Vane Excited Primary Jets by : Thomas Robert McClellan
Download or read book Experimental Investigation of Thrust Augmenting Ejectors Using Vane Excited Primary Jets written by Thomas Robert McClellan and published by . This book was released on 1982 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation has been conducted to evaluate the entrainment characteristics of a thrust augmenting ejector, with a small, oscillating airfoil inserted in the potential core of the primary jet. Velocity distributions were measured across the width of the jet, at downstream distances of 20 and 40 nozzle widths, with the jet exhausting into still air and with the jet exhausting into an instrumented ejector shroud for the following range of parameters: Pressure ratio 1.137 and 1.268, amplitude of oscillation 2.6 deg and 6.9 deg zero-to-peak frequency of oscillation 0, 20, 40 and 60 Hz. Static pressure distributions were measured within the shroud when the jector was installed. The results amplify previously conducted studies. Jet spreading and entrainment appear to increase with increasing amplitude and frequency of oscillation and to decrease with increasing nozzle pressure ratio. (Author).
Book Synopsis An Experimental Investigation of a Circular Thrust Augmenting Ejector by : Generoso C. Uhuad
Download or read book An Experimental Investigation of a Circular Thrust Augmenting Ejector written by Generoso C. Uhuad and published by . This book was released on 1985 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: A 4.4 in diameter circular ejector was tested to determine the effect on thrust augmentation ratio of the primary nozzle height and injection angle. Also tested were the effects of alternating primary nozzle injection angles, diffuser blowing and suction, inlet cross flow and low primary nozzle exit velocities on thrust augmentation. The results showed that both the primary nozzle injection angle and height affect the maximum thrust augmentation ratio attainable. A small amount of cross flow at the inlet increased the maximum thrust augmentation. The alternating primary nozzle injection angle arrangement did not increase the maximum thrust augmentation above that which was obtained using uniform primary nozzle injection angles. Diffuser blowing or suction did not provide an improvement in the maximum thrust augmentation above that which was obtained without diffuser boundary layer control. Finally, at low primary nozzle exit velocities, thrust augmentation increase as the nozzles were moved out along the inlet surface. The increase in thrust augmentation is attributed to the ability of the flow to remain attached to the inlet surface at low primary nozzle exit velocities thereby increasing the ejector effective mixing chamber length. (Author).
Book Synopsis An Experimental Investigation of a Circular Thrust Augmenting Ejector by : Generoso C. Uhuad (CAPT, USAF.)
Download or read book An Experimental Investigation of a Circular Thrust Augmenting Ejector written by Generoso C. Uhuad (CAPT, USAF.) and published by . This book was released on 1986 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Experimental Study of a Three-Dimensional Thrust Augmenting Ejector Using Laser Doppler Velocimetry by : National Aeronautics and Space Adm Nasa
Download or read book An Experimental Study of a Three-Dimensional Thrust Augmenting Ejector Using Laser Doppler Velocimetry written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-11-17 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flow field measurements were obtained in a three-dimensional thrust augmenting ejector using laser Doppler velocimetry and hot wire anemometry. The primary nozzle, segmented into twelve slots of aspect ratio 3.0, was tested at a pressure ratio of 1.15. Results are presented on the mean velocity, turbulence intensity, and Reynolds stress progressions in the mixing chamber of the constant area ejector. The segmented nozzle was found to produce streamwise vortices that may increase the mixing efficiency of the ejector flow field. Compared to free jet results, the jet development is reduced by the presence of the ejector walls. The resulting thrust augmentation ratio of this ejector was also calculated to be 1.34. Storms, Bruce Lowell Unspecified Center EJECTORS; FLOW MEASUREMENT; LASER DOPPLER VELOCIMETERS; REYNOLDS STRESS; THREE DIMENSIONAL FLOW; THRUST AUGMENTATION; TURBULENCE EFFECTS; VORTICES; ASPECT RATIO; EXHAUST VELOCITY; HOT-WIRE ANEMOMETERS; NOZZLE DESIGN; PRESSURE RATIO; V/STOL AIRCRAFT...
Book Synopsis An Experimental Study of Static Thrust Augmentation Using a 2-D Variable Ejector by : Eli Kedem
Download or read book An Experimental Study of Static Thrust Augmentation Using a 2-D Variable Ejector written by Eli Kedem and published by . This book was released on 1979 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: A short rectangular throat ejector was constructed and tested to determine the effects of a number of variables on thrust augmentation and mass augmentation. The variables included those associated with geometry (e.g., diffuser length/throat length, diffuser area ratio, diffuser sidewall angle, nozzle angles and positions) and those due to differences in primary mass flow rate distributions among the nozzles. There were two kinds of thrust augmentation that were calculated; the free thrust augmenting ratio and the isentropic thrust augmenting ratio. The free thrust augmenting ratio is the ratio of the ejector's measured thrust to the sum of the nozzles' measured thrust, if each of them were discharged separately to ambient pressure. The isentropic thrust augmenting ratio is the ratio of the ejector's measured thrust to the calculated thrust of the nozzles if discharged isentropically to the ambient pressure. A free thrust augmentating ratio as high as 1.63 and an isentropic thrust augmenting ratio of up to 1.29 were obtained. Mass augmentation which is the ratio of secondary flow to primary flow was in the range of 3.5 to 5. Some conclusions concerning design aspects were drawn also. They include the necessity of 3-D shrouding for the ejector's inlet and exit and the prevention of blowing high velocity air (primary and BLC flow) tangential to the ejector walls. (AUthor).
Book Synopsis An Experimental Study of Circular and Rectangular Thrust Augmenting Ejectors by : Steven G. Reznick (CAPT, USAF.)
Download or read book An Experimental Study of Circular and Rectangular Thrust Augmenting Ejectors written by Steven G. Reznick (CAPT, USAF.) and published by . This book was released on 1980 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Experimental Study of Rectangular and Circular Thrust Augmenting Ejectors by :
Download or read book An Experimental Study of Rectangular and Circular Thrust Augmenting Ejectors written by and published by . This book was released on 1981 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: A short rectangular ejector and two circular ejectors were tested to determine the effects of primary nozzle configuration and geometry on thrust augmentation. The primary nozzle configurations consisted primarily of slot nozzles which injected fluid parallel to the diffuser walls and achieved Coanda type flow at the throat. Results of the rectangular ejector tests indicate that thin plates installed in the mixing chamber or the diffuser, increase mixing but decrease thrust augmentation. A continuous slot nozzle, modified to create four discrete jets at the inlet, improved mixing and thrust augmentation compared to the original design. Thrust augmentation ratio increased from 1.4 to 1.58. The circular ejector primary nozzles consisted of a continuous slot 'torus' nozzle and individual slot nozzles which could be symmetrically placed around the inlet periphery. A nozzle configuration using 16 slot nozzles on the periphery of the inlet face gave the best performance. A thrust augmentation ratio of 2.0 was achieved.
Book Synopsis A Theoretical Study of Two Stage Thrust Augmenting Ejectors by : A. M. Abdel-Fattah
Download or read book A Theoretical Study of Two Stage Thrust Augmenting Ejectors written by A. M. Abdel-Fattah and published by . This book was released on 1984 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of theoretical assessment of two stage thrust augmenting ejectors are presented and compared with those of single stage ejectors. The mixing ducts were of constant cross sectional area, the flows at the inlet and exit planes of each stage were assumed to be uniform, and friction effects were ignored. It was found that staging the ejector increases thrust augmentation at all primary jet stagnation pressures, but is more effective in the low pressure range and with high ejector area ratios for any gas combination. With a Hot Rocket-Air combination, the benefit of staging is much less than with an unheated Air-Air combination, and does not appear to be of practical use.
Book Synopsis Experimental Thrust Augmentation of a Variable Geometry, Two-dimensional, Central Nozzle Ejector by : A. M. (Alastair M.) Drummond
Download or read book Experimental Thrust Augmentation of a Variable Geometry, Two-dimensional, Central Nozzle Ejector written by A. M. (Alastair M.) Drummond and published by . This book was released on 1962 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
