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Book Flow Field Over the Wing of a Delta Wing Fighter Model with Vortex Control Devices at Mach 0 6 To 1 2

Download or read book Flow Field Over the Wing of a Delta Wing Fighter Model with Vortex Control Devices at Mach 0 6 To 1 2 written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-17 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of a cooperative research program between NASA, McDonnell Douglas Corporation, and Wright Research and Development Center, a flow field investigation was conducted on a 7.52 percent scale windtunnel model of an advanced fighter aircraft design. The investigation was conducted in the Langley 16 ft Transonic Tunnel at Mach numbers of 0.6, 0.9, and 1.2. Angle of attack was varied from -4 degrees to 30 degrees and the model was tested at angles of sideslip of 0, 5, and -5 degrees. Data for the over the wing flow field were obtained at four axial survey stations by the use of six 5 hole conical probes mounted on a survey mechanism. The wing leading edge primary vortex exerted the greatest influence in terms of total pressure loss on the over the wing flow field in the area surveyed. A number of vortex control devices were also investigated. They included two different apex flaps, wing leading edge vortex flaps, and small large wing fences. The vortex flap and both apex flaps were beneficial in controlling the wing leading edge primary vortex. Bare, E. Ann and Reubush, David E. and Haddad, Raymond C. Langley Research Center DELTA WINGS; FIGHTER AIRCRAFT; FLOW DISTRIBUTION; SUBSONIC SPEED; TRANSONIC SPEED; VORTEX FLAPS; WIND TUNNEL MODELS; WIND TUNNEL TESTS; ANGLE OF ATTACK; FLOW VISUALIZATION; MACH NUMBER; PRESSURE DISTRIBUTION; SIDESLIP; TRANSONIC WIND TUNNELS...

Book NASA Technical Memorandum

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1992 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Use of Services for Family Planning and Infertility United States 1982

Download or read book Use of Services for Family Planning and Infertility United States 1982 written by Gerry E. Hendershot and published by . This book was released on 1988 with total page 982 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1982 statistics on the use of family planning and infertility services presented in this report are preliminary results from Cycle III of the National Survey of Family Growth (NSFG), conducted by the National Center for Health Statistics. Data were collected through personal interviews with a multistage area probability sample of 7969 women aged 15-44. A detailed series of questions was asked to obtain relatively complete estimates of the extent and type of family planning services received. Statistics on family planning services are limited to women who were able to conceive 3 years before the interview date. Overall, 79% of currently mrried nonsterile women reported using some type of family planning service during the previous 3 years. There were no statistically significant differences between white (79%), black (75%) or Hispanic (77%) wives, or between the 2 income groups. The 1982 survey questions were more comprehensive than those of earlier cycles of the survey. The annual rate of visits for family planning services in 1982 was 1077 visits /1000 women. Teenagers had the highest annual visit rate (1581/1000) of any age group for all sources of family planning services combined. Visit rates declined sharply with age from 1447 at ages 15-24 to 479 at ages 35-44. Similar declines with age also were found in the visit rates for white and black women separately. Nevertheless, the annual visit rate for black women (1334/1000) was significantly higher than that for white women (1033). The highest overall visit rate was for black women 15-19 years of age (1867/1000). Nearly 2/3 of all family planning visits were to private medical sources. Teenagers of all races had higher family planning service visit rates to clinics than to private medical sources, as did black women age 15-24. White women age 20 and older had higher visit rates to private medical services than to clinics. Never married women had higher visit rates to clinics than currently or formerly married women. Data were also collected in 1982 on use of medical services for infertility by women who had difficulty in conceiving or carrying a pregnancy to term. About 1 million ever married women had 1 or more infertility visits in the 12 months before the interview. During the 3 years before interview, about 1.9 million women had infertility visits. For all ever married women, as well as for white and black women separately, infertility services were more likely to be secured from private medical sources than from clinics. The survey design, reliability of the estimates and the terms used are explained in the technical notes.

Book NASA Scientific and Technical Publications

Download or read book NASA Scientific and Technical Publications written by and published by . This book was released on 1991 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Government Reports Announcements Index

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1994 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Technical Abstract Bulletin

Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Monthly Catalogue United States Public Documents

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1978 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Thrust induced Effects on a Pitching up Delta Wing Flow Field

Download or read book Thrust induced Effects on a Pitching up Delta Wing Flow Field written by Leon L. Van Dommelen and published by . This book was released on 1995 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neural network procedures were explored with the objectives to control a delta wing in the non-linear domain. Results show that neural networks are well suited to represent non-linear computed lift and pressure forces on delta wings. A model problem, the flare maneuver, suggests that neural network controllers can perform well for non-linear systems provided that suitable input and training data are provided to it.

Book Index to NASA Technical Publications

Download or read book Index to NASA Technical Publications written by United States. National Aeronautics and Space Administration and published by . This book was released on 1960-07 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book NASA Scientific and Technical Publications

Download or read book NASA Scientific and Technical Publications written by and published by . This book was released on 1987 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book An Experimental Investigation of the Passive Control of Reverse Delta Wing Vortex Flow Structure and Aerodynamics Characteristics

Download or read book An Experimental Investigation of the Passive Control of Reverse Delta Wing Vortex Flow Structure and Aerodynamics Characteristics written by Hongzhi Mou and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This thesis summarises an experimental study of a 65-sweep reverse delta wing (RDW) by using a seven-hole pressure probe and a two-component force balance at Re = 270,000. Dye water flow visualization was also conducted in order to better understand the flow structure. Particular emphasis was placed on the variation of vortex flow quantities and critical flow parameters such as the core circulation, total circulation, tangential velocity and axial core velocity with change in chordwise locations from x/c = 0.2 to x/c = 1.5 for [alpha] = 10°- 22°. Based on lift measurements, the RDW generated less lift from [alpha] = 8° to [alpha] = 35° in comparison with the conventional delta wing (DW). Hence, lift augmentation was attempted by attaching passive control devices such as a side edge strip (SES) and a leading edge strip (LES), made from aluminum strips with different widths, which were placed perpendicularly to the wing's bottom surface. The flow field scans showed that the vortex flow underwent diffusion while it progressed in the chordwise direction. The size of the separated flow region, which originated from the spanwise vortex breakdown, increased with the angle of attack. Compared to a baseline RDW, RDW with SES generated a pair of more concentrated vortices with a higher core and total circulation values. Compared to a baseline RDW, the lift coefficient generated by the RDW with a 1.5% c SES and a 3% c SES increased by 0.18 to 0.28 on average, for angles of attack ranging from 0° to 40°. In addition, 1.5% c and 3% c SES boosted the wing's lift-to-drag ratio, for an average of 24% and 5%, respectively, from angles of attack of 10° to 20°. The dye flow visualization showed that the vortex flow generated by the RDW was located outside of the wing's surface and the vortex generated by the DW is located above the wing surface, in which suggesting the vortex lift is not applicable to a RDW. " --