ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • AERODYNAMICS  (880)
  • 1980-1984  (342)
  • 1970-1974  (519)
  • 1955-1959  (19)
  • 1945-1949
  • 1980  (342)
  • 1974  (299)
  • 1970  (220)
  • 1957  (19)
Collection
Years
  • 1980-1984  (342)
  • 1970-1974  (519)
  • 1955-1959  (19)
  • 1945-1949
Year
  • 1
    Publication Date: 2005-11-27
    Description: Jet induced flow field effects on V/STOL aircraft in subsonic transition flight
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 683-702
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2005-11-27
    Description: Iterative method for designing supersonic body of revolution from surface pressure distribution
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 75-84
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2005-11-27
    Description: Ground wind loads on reusable space shuttles
    Keywords: AERODYNAMICS
    Type: SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 2 JUL. 1970; P 143-160
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-27
    Description: Space shuttle buffeting and aerodynamic noise
    Keywords: AERODYNAMICS
    Type: SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 2 JUL. 1970; P 238-247
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2005-11-27
    Description: Ducted fan interference analysis for transport aircraft
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 703-719
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2005-11-27
    Description: Time-dependent numerical method for blunt body flow field solutions
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 177-195
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2005-11-27
    Description: Prediction methods for boundary layer and flow field characteristics in shock wave-boundary layer interaction
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 515-539
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2005-11-27
    Description: Numerical analysis of three dimensional viscous supersonic flow fields about slender bodies
    Keywords: AERODYNAMICS
    Type: NASA, WASHINTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 265-321
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2005-11-27
    Description: Method of characteristics for computerized design of optimal supersonic inlets
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 569-581
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2005-11-27
    Description: Aerodynamic method of characteristics for pressure field calculations about wing-body combinations
    Keywords: AERODYNAMICS
    Type: L METHODS IN AIRCRAFT AERODYN. 1970; P 215-227
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-27
    Description: Numerical analysis of propeller-wing flow interaction with slipstreams
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 721-742
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2005-11-27
    Description: Wind tunnel simulation of ground wind shear and turbulence spectra and application to space shuttle launching
    Keywords: AERODYNAMICS
    Type: NASA. LEWIS RES. CENTER SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 2 JUL. 1970; P 161-175
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2005-11-27
    Description: Lift and pressure distribution calculations for winged body with leading edge vortices
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 113-129
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2005-11-27
    Description: Finite difference solution for compressible turbulent boundary layer equations of swept slab with leading edge blowing
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 417-472
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2005-11-27
    Description: Review of prediction methods for compressible turbulent boundary layers
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 355-416
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2005-11-27
    Description: Finite difference analysis of hyperbolic partial differential equations
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 245-264
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2005-11-27
    Description: Computer programs for predicting flow field properties in supersonic and hypersonic inlets
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 583-595
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2005-11-27
    Description: Wing-body interference theory for calculating lift slope and stability at hypersonic speed
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 101-111
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2005-11-27
    Description: Numerical lifting surface theory with spanwise distribution of control points
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 1-35
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2005-11-27
    Description: Method of characteristics for flow field analysis on elliptical winged body
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 159-176
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2005-11-27
    Description: Finite element method for predicting aerodynamic characteristics of wing-body combinations
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 37-51
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2005-11-27
    Description: Potential flow solution for VTOL inlets in static and crossflow operation
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 659-681
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2005-11-27
    Description: Analysis of secondary flow effects in propeller and rotor boundary layers
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 473-514
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-27
    Description: Finite difference method for transonic flow solution in axial stator
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 597-621
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2005-11-27
    Description: Method of characteristics for calculating oblique shock wave interaction with turbulent boundary layer
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 541-567
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2005-11-27
    Description: Aerodynamic forces in supersonic panel flutter
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 335-353
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-27
    Description: Static laminar Coanda jet flow around circular cylinder with external flow entrainment
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 197-214
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2005-11-27
    Description: Correlation method for estimating pressure distribution over elliptic supersonic cones
    Keywords: AERODYNAMICS
    Type: L. METHODS IN AIRCRAFT AERODYN. 1970; P 85-99
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2005-11-27
    Description: Calculation methods for predicting transonic aerodynamic characteristics of wing-body combinations
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON ANAL. METHODS IN AIRCRAFT AERODYN. 1970; P 53-73
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2009-11-17
    Description: Prediction of steady and unsteady airloads on space shuttles
    Keywords: AERODYNAMICS
    Type: NASA. LEWIS RES. CENTER SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 2 JUL. 1970; P 223-237
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2011-08-16
    Description: Retrorocket jet size and structure for scientific instruments soft Mars landing, estimating off- optimum supersonic jet interaction with quiescent atmosphere
    Keywords: AERODYNAMICS
    Type: ; STITUTION OF ENGINEE
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2011-08-16
    Description: Scaling relations showing effects of ballistic coefficient, flight path angle and inverse atmospheric scale height on heating of ballistic entry bodies
    Keywords: AERODYNAMICS
    Type: ; STITUTION OF ENGINEE
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2011-08-16
    Description: Wind tunnel apparatus for reproducing coning and spinning motions of bodies of revolution, using six-component strain gage balance for aerodynamic forces
    Keywords: AERODYNAMICS
    Type: ; UGREVUE(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Heat transfer and shock wave shapes about blunt slender cones in viscous-inviscid coupling hypersonic flow
    Keywords: AERODYNAMICS
    Type: ; UGREVUE(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2011-08-16
    Description: Heat transfer from turbulent boundary layer interacting with shock and expansion waves in supersonic flow
    Keywords: AERODYNAMICS
    Type: ; UGREVUE(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2011-08-16
    Description: Spheres drag coefficient at hypersonic Mach numbers for near free molecular flow
    Keywords: AERODYNAMICS
    Type: ; UGREVUE(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2011-08-16
    Description: Forces on two dimensional oscillating airfoil in subsonic compressible wind tunnel flow, solving partial differential equation for pressure potential by integral transform technique
    Keywords: AERODYNAMICS
    Type: ; YAL SOCIETY (
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2011-08-16
    Description: An unsteady lifting-surface theory is developed for the calculation of the airload on a semi-infinite-span thin wing in a compressible flow due to interaction with an oblique gust. By using the solutions obtained for a two-dimensional wing, the problem is formulated so that the unknown is taken to be the difference between the airload on the semi-infinite wing and that on a two-dimensional wing under the same gust conditions. Since this airload difference is nonzero only near the wing tip, the control points need be distributed in the tip region only; this significantly simplifies the numerical procedure. Results are presented for a wing with rectangular tip. The implication for noise and unsteady loads due to blade-vortex interaction for helicopter rotors is discussed.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; Dec. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2011-08-16
    Description: Limitations concerning the possibility to simulate all the significant flow and thermal phenomena occurring during the entry of a space vehicle into a planetary atmosphere make it necessary to rely on computational analyses to obtain the required data for the design of the spacecraft needed for the NASA missions planned for the next two decades. 'Benchmark' computer programs concerned with complete, detailed, and accurate computational solutions of entry problems are considered along with programs representing engineering approximations for cases in which the accuracy provided by the benchmark programs is not needed. The information obtainable by computational analysis has to be supplemented by actual flight experience in order to meet the goals of the NASA entry-technology program. The individual space missions planned for the coming years are examined together with the possibilities for obtaining the data needed to satisfy the entry requirements in each case.
    Keywords: AERODYNAMICS
    Type: Astronautics and Aeronautics; 12; Dec. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2011-08-16
    Description: The analysis of sound fields from arbitrary source distributions in terms of Legendre and spherical Hankel functions is well known. The purpose of this paper is to extend this classical method of analysis to environments such as jet flows where flow and flow gradients are inherently present. The wave-equation governing the radiation of sound in such an environment is derived. The steady state flow and flow gradients in the axial and transverse directions appear as coefficients in the terms of the wave-equation. A semi-numerical method is used to solve the wave-equation in terms of modified spherical harmonics yielding the phase velocities and the directivities of an infinite set of modes. The directivity of each mode is obtained in terms of modified Legendre functions by numerical integration. Some results of these directivity and phase-velocity calculations are presented for a limited number of frequency and flow parameters. Both convective and shear refraction are shown to be important.
    Keywords: AERODYNAMICS
    Type: Journal of Sound and Vibration; 36; Sept. 8
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2011-08-16
    Description: A general equation governing aerodynamic sound generation in the presence of solid boundaries is derived. It is shown that all the theories in the literature appear as special cases of this general equation. Derived special equations for propeller and fan noise are likewise shown to be more general than the conventional equations in that they make allowance for variation in retarded time over the blade surfaces.
    Keywords: AERODYNAMICS
    Type: Acoustical Society of America; vol. 56
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2011-08-16
    Description: A method for automatic numerical generation of a general curvilinear coordinate system with coordinate lines coincident with all boundaries of a general multi-connected region containing any number of arbitrarily shaped bodies is presented. With this procedure the numerical solution of a partial differential system may be done on a fixed rectangular field with a square mesh with no interpolation required regardless of the shape of the physical boundaries, regardless of the spacing of the curvilinear coordinate lines in the physical field, and regardless of the movement of the coordinate system. Numerical solutions for the lifting and nonlifting potential flow about Joukowski and Karman-Trefftz airfoils using this coordinate system generation show excellent comparison with the analytic solutions. The application to fields with multiple bodies is illustrated by a potential flow solution for multiple airfoils.
    Keywords: AERODYNAMICS
    Type: Journal of Computational Physics; 15; July 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2011-08-16
    Description: The propagation of waves of acoustic frequencies in curved ducts of rectangular cross section is studied for the first four modes. The analysis makes use of Bessel functions of the order (n + 1/2) to construct curves of wavenumber in the duct versus imposed wavenumber and to determine the profile of vibrational velocities. A wide range of duct widths and unrestricted radii of curvature have been considered. The characteristics of motion in a bend are compared with propagation of waves in a straight duct, and important differences in the behavior of waves are noted.
    Keywords: AERODYNAMICS
    Type: Acoustical Society of America; vol. 56
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A scanning laser Doppler velocimeter was used to measure the axial velocity defect in the cores of trailing vortices behind a lifting airfoil of rectangular planform. Data were obtained at several different angles of attack and downstream distances ranging from 30 to 1000 chord lengths. The test was designed to obtain continuous data from the near field into the far field while removing uncertainties associated with the interpretation of data obtained by the hydrogen bubble technique. The measured velocities of V sub x/U sub infinity are compared with those predicted. The agreement is remarkably good over the entire range of downstream distances, which supports the credibility of calculating axial velocities using the results of Moore and Saffman (1973).
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2011-08-16
    Description: A backscatter laser Doppler velocimeter which simultaneously senses the axial and the tangential components of the velocity has been used to measure the velocity distributions in the near wake of a swept wing semispan transport model in a wind tunnel. The model configuration included nacelles, pylons, antishock bodies, and wing flaps which could be deflected 27 deg. Typical wake vortex velocity profiles are presented for the flaps-retracted and the flaps-deployed 27 deg configurations, respectively.
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft; 11; June 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2011-08-16
    Description: A primary factor governing hypersonic flowfield characteristics of blunt vehicles entering planetary atmospheres is the normal shock density ratio. Hence, a means of duplicating or simulating the high density ratios experienced during planetary entry is needed. One facility having the capability of generating a range of hypersonic-hypervelocity flow conditions in arbitrary test gases is the expansion tube. Preliminary shock shape results obtained in the Langley 6-in. expansion tube at hypersonic conditions are presented. Normal shock density ratios from approximately 4 to 19 were generated using helium, air, and CO2 test gases at freestream velocities from 5 to 7 km/sec. Test models were a flat-faced cylinder and the Viking aeroshell.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; Mar. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2011-08-16
    Description: Some results are described for a lifting rectangular wing centrally located on a circular-cylindrical body. This simple configuration has been utilized in order to assess the merits of a mapping technique for wing-body configurations. The procedure employed makes use of a coordinate transformation to simplify specification of the surface boundary condition in the computation of the flow about the wing. The method can be extended to incorporate wing sweep, finite length body of noncircular cross section, and arbitrary wing placement; however, these extensions involve a considerable increase in complexity of the problem.
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft; 11; Apr. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A mathematical model of the vortex flow over a slender sharp-edged delta wing is proposed, and is shown to provide good agreement with the experiment. Although the technique requires experimental data in the form of the vortex core locations, it does account for the previously ignored mass entrainment of the vortex core.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; Jan. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Schlieren photographs of shock interference heating for space shuttles
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 1 JUL. 1970; P 338-389
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2011-08-16
    Description: Boundary layer transition on lifting reentry vehicles at high angles of attack
    Keywords: AERODYNAMICS
    Type: NASA, WASHINGTON SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 1 JUL. 1970; P 445-462
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2011-08-16
    Description: Wind tunnel tests of aerodynamic stability, boundary layer transition, and heat transfer in space shuttle orbiters
    Keywords: AERODYNAMICS
    Type: SPACE TRANSPORTATION SYSTEM TECHNOL. SYMP., VOL. 1 JUL. 1970; P 142-193
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2011-08-16
    Description: Supersonic skin friction measurements in grit type boundary layer transition trips with zero heat transfer
    Keywords: AERODYNAMICS
    Type: ; SEARCH(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Radiation effects on viscous hypersonic low density stagnation flow using two layer model, calculating flow field and heat transfer coefficient
    Keywords: AERODYNAMICS
    Type: ; ACE(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Missile oscillations in plane during pitching moment hysteresis, discussing test coefficients suitability for predicting motion
    Keywords: AERODYNAMICS
    Type: ; RO(
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2011-08-16
    Description: Off-centerline heating on lee surface of supersonic delta wing with separation and vortex initiation at leading edge
    Keywords: AERODYNAMICS
    Type: ; ADEMIE DES SCIENCES
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2011-08-16
    Description: Adiabatic flow coefficient in supersonic nozzle with choked flow conducted over throat Reynolds number range
    Keywords: AERODYNAMICS
    Type: ; ADEMIE DES SCIENCES
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2011-08-16
    Description: Electron concentration profiles in blunt nose vehicle shock layer during atmospheric near orbital entry at high altitudes, using finite rate chemistry
    Keywords: AERODYNAMICS
    Type: ; ADEMIE DES SCIENCES
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2011-08-16
    Description: Results are presented of a procedure for estimating stability and control parameters from flight data, by using maximum likelihood methods employing an interactive computer system, which was established at the NASA Langley Research Center. Problems encountered are discussed.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 49-76
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2011-08-16
    Description: A maximum likelihood estimator for a linear system with state and observation noise is developed to determine stability and control derivatives from flight data obtained in the presence of turbulence. The formulation for the longitudinal short-period mode is presented briefly, including a special case that greatly simplifies the problem if the measurement noise on one signal is negligible. The effectiveness and accuracy of the technique are assessed by applying it first to simulated flight data, in which the true parameter values and state noise are known, then to actual flight data obtained in turbulence. The results are compared with data obtained in smooth air and with wind-tunnel data. The complete maximum likelihood estimator, which accounts for both state and observation noise, is shown to give the most accurate estimate of the stability and control derivatives from flight data obtained in turbulence. It is superior to the techniques that ignores state noise and to the simplified method that neglects the measurement noise on the angle-of-attack signal.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 77-114
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2011-08-16
    Description: Two methods for extracting stability derivatives from flight data are compared. A modified Newton-Raphson quasilinearization minimization technique and a digital-analog (hybrid) matching technique were used to analyze the same data maneuvers obtained from two aircraft. About 70 maneuvers from an F-111E aircraft were analyzed over a Mach number range of 0.3 to 2.0 and an angle of attack range of 3 to 19 degrees. About 20 maneuvers were analyzed for the X-24A lifting body at Mach numbers of 0.5, 0.8, and 0.9, and an angle of attack range of 4 to 13 degrees. Stability derivatives were extracted from these maneuvers and the results from the two techniques, along with wind tunnel results, were compared.
    Keywords: AERODYNAMICS
    Type: NASA. Flight Res. Center Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 43-48
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2011-08-16
    Description: Description of a correlation, derived from water tank measurements in the wake of wings towed under water, that makes it possible to predict the downstream distance behind an aircraft in flight where its trailing vortex will begin to decay. Comparisons of measured and predicted data are discussed.
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft; 11; Nov. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2011-08-16
    Description: The artificial viscosity method of Kuwahara and Takami (1973) is used to calculate the roll-up of trailing vortices behind a number of practical aerodynamic configurations. Where possible, the results are compared for core location with available experimental data.
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft; 11; Nov. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2011-08-16
    Description: Electron density profiles which include the effect of an ablated sodium impurity were computed for the boundary layer on a blunt-nosed body re-entering the atmosphere at 7.62 km/sec. Profiles are computed from the nose to a distance of four diameters along the RAM C-payload. A finite-difference, laminar, nonequilibrium chemistry boundary-layer program was used. Comparison of theory with S-band diagnostic antenna results, electron concentration deduced from X- and C-band attenuation data, and Langmuir probe data at several different aft body locations show that agreement is good at high altitude. At the lower altitudes there is disagreement between theory and S-band antenna data where the apparent discrepancy is attributed to the three-body recombination rate constant used for deionization of sodium coupled with the effect of angle of attack.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; June 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: The growth of the field of system identification is discussed along with changes in methodology which have taken place in recent years. The similarity between pattern recognition and system identification is pointed out, involving the modelling in the latter and the feature selection problem in the former. It is stated that once a model is formulated, including the disturbances and measurement errors, the parameter finding can be formulated as a statistical estimation problem. The various techniques and their application are discussed.
    Keywords: AERODYNAMICS
    Type: NASA. Flight Res. Center Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 381-385
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A state-of-the-arts review is given for the field of system identification. Progress in the field is traced from the early models of dynamic systems by Sir Isaac Newton up to the present day use of advanced techniques for numerous applications.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 375-379
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: The criterion that is proposed is an expected value of the mean square response error as an alternative to testing a model against new data. Modeling with respect to this new criterion does not change the estimate for a given model format from a maximum likelihood estimate or mean square response error estimate. The new criterion does, however, provide a means of comparing models with different formats and varying complexity. A numerical example is used to illustrate the application of the proposed criteria and the problem of searching for the best model. For all but the most trivial system identification problems, it is shown that a prohibitive number of combinations of terms of the model must be investigated to ensure the final model is best.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 291-313
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2011-08-16
    Description: An error analysis program based on an output error estimation method was used to evaluate the effects of sensor and instrumentation errors on the estimation of aircraft stability and control derivatives. A Monte Carlo analysis was performed using simulated flight data for a high performance military aircraft, a large commercial transport, and a small general aviation aircraft for typical cruise flight conditions. The effects of varying the input sequence and combinations of the sensor and instrumentation errors were investigated. The results indicate that both the parameter accuracy and the corresponding measurement trajectory fit error can be significantly affected. Of the error sources considered, instrumentation lags and control measurement errors were found to be most significant.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 261-280
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2011-08-16
    Description: The parameter identification scheme being used is a differential correction least squares procedure (Gauss-Newton method). The position, orientation, and derivatives of these quantities with respect to the parameters of interest (i.e., sensitivity coefficients) are determined by digital integration of the equations of motion and the parametric differential equations. The application of this technique to three vastly different sets of data is used to illustrate the versatility of the method and to indicate some of the problems that still remain.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 191-195
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2011-08-18
    Description: An interactive model for numerical computation of complicated two-dimensional flowfields including regions of reversed flow is proposed. The present approach is one of dividing the flowfield into three regions, in each of which a simplified mathematical model is applied: (1) outer, supersonic flow for which the full potential equation (hyperbolic) is used; (2) viscous, laminar layer in which the compressible boundary-layer model (parabolic) is used; and (3) recirculating flow modeled by the incompressible Navier-Stokes equations (elliptic). For matching of the numerical solutions in the three layers, two interaction models are developed: one for pressure interaction, the other for interaction between the shear layer and the recirculating flow. The uniform solution for the whole flowfield is then obtained by iteration of the local solutions under the constraints imposed by matching. The three-layer interactive model is used for solution of the flowfield past an asymmetric cavity. The method is shown to be capable of dealing with backflow without encountering problems at separation, characteristic to the boundary-layer approach.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 18; Nov. 198
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-17
    Description: The recently observed phenomenon of high noise radiation from the side edges of flaps in flow is investigated by way of a simple two-dimensional model problem. The model is based upon a physical picture of boundary layer vorticity being swept around the edge by spanwise flow on the flap. The model problem is developed and solved and the resulting noise radiation calculated. Further, a mathematical condition for the vortex to be captured by the potential flow and swept around the edge is derived. The results show that the sound generation depends strongly upon the strength of the vorticity and distance from the edge and that it can be more intense than the more common trailing edge noise source in agreement with the experimental observations.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 18; May 1980
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-17
    Description: The paper describes the computation of two-dimensional, subsonic, diverging internal flows and how they differ from the corresponding converging flows. Such diverging or decelerating flows occur in such obvious places as subsonic diffusers and inlets; however, such flows also occur in supersonic nozzles in the presence of a normal shock. The flow instability and its relation to the numerical method used, boundary conditions, and viscous effects are assessed both analytically and numerically. The inviscid flow is shown to be physically unstable and a poor representation of the true viscous flow.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 18; May 1980
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-17
    Description: Three examples of advances in computational aerodynamics; (1) three-dimensional inviscid transonic analysis, (2) design calculations for wings, and (3) the computation of viscous-induced aileron buzz, are reviewed. Attention is given to wing surface pressures, design optimization, computer memory, speed and advanced solution methods on parallel computer architecture. It is determined that many implicit approximate-factorization schemes, that have been developed for Navier-Stokes equations, can be coded to run efficiently on microprocessors.
    Keywords: AERODYNAMICS
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-18
    Description: A technique employed by Prandtl and Munk is adapted for the case of a wing in flapping motion to determine its lift distribution. The problem may be reduced to one of minimizing induced drag for a specified and periodically varying bending moment at the wing root. It is concluded that two wings in close tandem arrangement, moving in opposite phase, would eliminate the induced aerodynamic losses calculated
    Keywords: AERODYNAMICS
    Type: Aeronautical Journal; 84; July 198
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2011-08-17
    Description: The turbulence downstream of a rapid contraction is calculated for the case when the turbulence scale can have the same magnitude as the mean-flow spatial scale. The approach used is based on the formulation of Goldstein (1978) for turbulence downstream of a contraction, with the added assumptions of a parallel mean flow at downstream infinity and turbulence calculated far enough downstream so that the nonuniformity of the mean flow field has decayed, and by treating the inverse contraction ratio as a small parameter. Consideration is given to the large-contraction-ratio and classical rapid-distortion theory limits, and to results at an arbitrary contraction ratio. It is shown that the amplification effect of the contraction is reduced when the spatial scale of the turbulence increases, with the upstream turbulence actually suppressed for a contraction ratio less than five and a turbulence spatial scale greater than three times the transverse dimensions of the downstream channel.
    Keywords: AERODYNAMICS
    Type: Journal of Fluid Mechanics; 98; June 12
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-17
    Description: It is noted that so far most systematic investigations on the lee side flow over delta wings at supersonic speeds are concerned with flat upper surfaces. On the basis of these results, the paper makes an attempt to characterize the different types of flow over a wing with a delta-shaped upper surface by varying a number of parameters. It is concluded that the work should be considered a first step toward systematizing the flow over delta-shaped lee sides as well.
    Keywords: AERODYNAMICS
    Type: Zeitschrift fuer Flugwissenschaften und Weltraumforschung; 4; Mar
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2012-05-22
    Description: The aerodynamic effectiveness of various propulsive lift concepts to provide for the low speed performance and control required for short takeoff and landing aircraft is discussed. The importance of the interrelationship between the propulsion system and aerodynamic components of the aircraft is stressed. The relative effectiveness of different lift concepts was evaluated through static and wind tunnel tests of various aerodynamic models and propulsion components, simulations of aircraft, and in some cases, flight testing of research aircraft incorporating the concepts under study. Results of large scale tests of lift augmentation devices are presented. The results of flight tests of STOL research aircraft with augmented jet flaps and rotating cylinder flaps are presented to show the steeper approach flight paths at low forward speeds.
    Keywords: AERODYNAMICS
    Type: AGARD V/STOL Aerodyn.; 6 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2011-08-16
    Description: A numerical generalized-capacity-matrix technique is developed for application to aerodynamic flow computations. This technique allows the very fast direct (noniterative) numerical elliptic solvers to be used in problems with arbitrary internal boundaries and with a wide class of boundary conditions, including numerical application of the Kutta condition on an airfoil without iteration. Accuracy, speed, and usefulness of the technique are demonstrated with linear problems for potential flows over airfoil shapes. The method's main advantages, however, can be exploited within iterative procedures for a variety of complex flow problems governed by systems of equations not necessarily elliptic or linear.
    Keywords: AERODYNAMICS
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2011-08-16
    Description: A fast direct (noniterative) 'Cauchy-Riemann Solver' is developed for solving the finite-difference equations representing systems of first-order elliptic partial differential equations in the form of the nonhomogeneous Cauchy-Riemann equations. The method is second-order accurate and requires approximately the same computer time as a fast cyclic-reduction Poisson solver. The accuracy and efficiency of the direct solver are demonstrated in an application to solving an example problem in aerodynamics: subsonic inviscid flow over a biconvex airfoil. The analytical small-perturbation solution contains singularities, which are captured well by the computational technique. The algorithm is expected to be useful in nonlinear subsonic and transonic aerodynamics.
    Keywords: AERODYNAMICS
    Type: Journal of Computational Physics; 15; May 1974
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2011-08-16
    Description: Some recent experience at Ames Research Center in the estimation of aerodynamic coefficients for the Lear-Jet and the Augmentor Wing Jet STOL Research Aircraft is reviewed. The coefficients estimated from flight data are compared with values based on large-scale wind-tunnel tests. The results obtained by the regression and quasilinearization identification techniques are also compared. The regression method generally provides the lower standard deviation in the coefficient estimates and provides the better fit to the wind-tunnel values. The addition of nonlinear terms in the aerodynamic equations decreases the difference between the estimated and measured time histories but also increases the standard deviation in the estimated coefficient values.
    Keywords: AERODYNAMICS
    Type: Parameter Estimation Tech. and Appl. in Aircraft Flight Testing; p 125-148
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Publication Date: 2011-08-16
    Description: Discussion of the local heating effect on the lee-side control flaps of supersonic configurations due to the interaction between vortices and leeward control surfaces at an angle of attack. Considerations are given for an appropriate positioning of control flaps to alleviate such interactions and the resulting thermal effect. Tests are carried out on a sharp right circular cone with two types of flap configurations in a study of oil flow patterns about the cone at selected angles of attack. Splitting of flaps and moving them to positions away from the symmetry plane did reduce the heating but also reduced the average flap pressure and increased flow complexity.
    Keywords: AERODYNAMICS
    Type: Journal of Spacecraft and Rockets; 11; Mar. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A new static probe design is described in which the static holes are located much closer to the tip than in conventional probes. The new probe shows promise for use in some situations where conventional probes become highly inaccurate. An additional advantage of the new design is that, when used in static pressure survey rakes, the probes can be located much closer together than in conventional designs and still ensure that disturbances from neighboring probe tips do not affect the static readings.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 12; Apr. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Presented data on vortex-induced heating in a cone-cylinder body at Mach 6 show that the most severe heating need not occur as a result of the interaction of the primary vortices with the lee surface, even though this interaction produces a large, well-defined featherline oil smear. It is pointed out that the severity of vortex-induced heating is extremely sensitive to Reynolds number and geometry and that there exists a 'threshold Reynolds number' below which vortex-induced heating decreases abruptly.
    Keywords: AERODYNAMICS
    Type: Journal of Spacecraft and Rockets; 11; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Publication Date: 2011-08-16
    Description: The changes in aerodynamic characteristics due to real-gas effects associated with high speed flight (characterized by large shock density ratios) are primarily the result of changes in surface pressures acting on the forebody. The surface pressures are affected by a change in shock density ratio (real-gas effects) in two ways. First, the level of pressure at the stagnation point relative to freestream dynamic pressure is changed, and second, the distribution of surface pressure relative to stagnation-point pressure is changed. The density-ratio effect on the stagnation point pressure level can be estimated by considering the flow of a perfect gas about a blunt body.
    Keywords: AERODYNAMICS
    Type: Journal of Spacecraft and Rockets; 11; Jan. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Starting criterion for hypersonic inlets with large turbulent boundary layers, considering total pressure recovery from all shock and viscous losses
    Keywords: AERODYNAMICS
    Type: ; YSICA STATUS SOLIDI
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: One dimensional compound compressible nozzle flow solution dependence on initial conditions and nozzle geometry, discussing applications to bypass turbojets and solid propellant motors
    Keywords: AERODYNAMICS
    Type: ; ADEMIE DES SCIENCES
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2012-05-22
    Description: An analysis of the development and technological applications of V/STOL aircraft is presented. The use of V/STOL aircraft to overcome the limitations of conventional aircraft is discussed. The aspects of V/STOL aircraft which are considered are: (1) economic penalties of propulsive lift, (2) advantages of propulsive lift, (3) potential improvements in V/STOL aircraft, (4) the aerodynamics of V/STOL aircraft, and (5) proposals for additional research in V/STOL development.
    Keywords: AERODYNAMICS
    Type: AGARD V/STOL Aerodyn.; 13 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2012-05-22
    Description: Wind effects on launch vehicle and equations of motion of vehicle
    Keywords: AERODYNAMICS
    Type: AGARD WIND EFFECTS ON LAUNCH VEHICLES FEB. 1970; P 199-226
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2012-05-22
    Description: Aerodynamic loads produced by winds and launch vehicle designing
    Keywords: AERODYNAMICS
    Type: AGARD WIND EFFECTS ON LAUNCH VEHICLES FEB. 1970; P 75-114
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2011-08-18
    Description: The thin-layer approximation is extended to an axial corner that is formed by the intersection of two perpendicular plates, one of which has an inclination angle with respect to the free stream. A computer code developed by Hung and MacCormack (1978) is modified for the thin-layer approximation, and a case with Mach 5.9 and a wedge angle of 6 deg is computed. In addition, it is shown that it is not necessary to solve the complete Navier-Stokes equations for a three-dimensional high-Reynolds-number corner flow.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 18; Dec. 198
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2011-08-17
    Description: The effects of ablated nose shapes on the flowfield solutions are studied, using a time-dependent finite-difference method developed by Kumar, et al. (1979). Solutions are obtained for the laminar flow of a radiating mixture of H-He in chemical equilibrium past a blunt axisymmetric body at zero angle of attack. The freestream conditions correspond to a point on a typical Jovian entry trajectory, and the initial probe shape is a 45-deg half-angle spherically blunted cone. It is found that as nose bluntness increases, the following occur: in the nose region, shock standoff distances and radiative heating rates increase substantially; surface pressure level increases, but convective heating rates decrease.
    Keywords: AERODYNAMICS
    Type: AIAA Journal; 18; June 198
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-17
    Description: This paper presents a unified treatment of the effect of lift on peak acceleration during atmospheric entry. Earlier studies were restricted to different regimes because of approximations invoked to solve the same transcendental equation. This paper shows the connection between the earlier studies by employing a general expression for the peak acceleration and obtains solutions to the transcendental equation without invoking the earlier approximations. Results are presented and compared with earlier studies where appropriate.
    Keywords: AERODYNAMICS
    Type: Journal of Spacecraft and Rockets; 17; Mar
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2011-08-18
    Keywords: AERODYNAMICS
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2016-06-07
    Description: The development of a three axis stabilized balloon platform capable of being operated in three modes of increasing accuracy is discussed. The system relies on angular motion sensing for primary feedback with linear accelerometers, magnetometers, and a star sensor for positional information. When under primary control the system will acquire and stabilize on any accessible part of the celestial sphere. A video verification system is included to provide pointing confirmation. Under improved accuracy control, the star sensor is used to lock onto a target star.
    Keywords: AERODYNAMICS
    Type: NASA. Ames Res. Center Telescope Systems for Balloon-Borne Res.; p 284-293
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2016-06-07
    Description: The establishment and functions of the AFCRL balloon operations facility are discussed. The types of research work conducted by the facility are defined. The facilities which support the balloon programs are described. The free balloon and tethered balloon capabilities are analyzed.
    Keywords: AERODYNAMICS
    Type: NASA. Ames Res. Center Telescope Systems for Balloon-Borne Res.; p 160-164
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Publication Date: 2016-06-07
    Description: A configuration has been developed for a long-life balloon platform to carry pointing telescopes weighing as much as 80 pounds (36 kg) to point at selected celestial targets. A platform of this configuration weighs about 375 pounds (170 kg) gross and can be suspended from a high altitude super pressure balloon for a lifetime of several months. The balloon platform contains a solar array and storage batteries for electrical power, up and down link communications equipment, and navigational and attitude control systems for orienting the scientific instrument. A biaxial controller maintains the telescope attitude in response to look-angle data stored in an on-board computer memory which is updated periodically by ground command. Gimbal angles are computed by using location data derived by an on-board navigational receiver.
    Keywords: AERODYNAMICS
    Type: NASA. Ames Res. Center Telescope Systems for Balloon-Borne Res.; p 136-144
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Publication Date: 2016-06-07
    Description: A system capable of pointing a balloon-borne telescope at selected celestial objects to an accuracy of approximately 10 arc minutes for an extended period (weeks to months) without reliance on telemetry is described. A unique combination of a sun/star tracker, an on-board computer, and a gyrocompass is utilized for navigation, source acquisition and tracking, and data compression and recording. The possibilities for intelligent activities by the computer are also discussed.
    Keywords: AERODYNAMICS
    Type: NASA. Ames Res. Center Telescope Systems for Balloon-Borne Res.; p 71-80
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Publication Date: 2016-06-07
    Description: An overview of an experimental and analytical research program underway for studying the aeroelastic and dynamic characteristics of tilt-rotor VTOL aircraft is presented. Selected results from several investigations of scaled models in the transonic dynamics tunnel, as well as some results from a test of a flight-worthy proprotor in the full-scale wind tunnel are shown and discussed with a view toward delineating various aspects of dynamic behavior peculiar to proprotor aircraft. Included are such items as proprotor/pylon stability, whirl flutter, gust response, and blade flapping. Theoretical predictions are shown to be in agreement with the measured stability and response behavior.
    Keywords: AERODYNAMICS
    Type: Its Rotorcraft Dyn.; p 171-184
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2016-06-07
    Description: A nine degrees-of-freedom theoretical model was developed for investigations of the dynamics of a proprotor operating in high inflow axial flight on a cantilever wing. The theory is described, and the results of the analysis are presented for two proprotor configurations: a gimballed, stiff-inplane rotor, and a hingeless, soft-inplane rotor. The influence of various elements of the theory are discussed, including the modeling used for the blade and wing aerodynamics, and the influence of the rotor lag degree of freedom. The results from full-scale tests of the two proprotors are presented and compared with the theoretical results.
    Keywords: AERODYNAMICS
    Type: Its Rotorcraft Dyn.; p 159-169
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Publication Date: 2017-10-02
    Description: Theoretical studies of aerodynamic forces on winglets shed considerable light on the mechanism by which these devices can reduce drag at constant total lift and on the necessity for proper alignment and cambering to achieve optimum favorable interference. Results of engineering studies, wind tunnel tests and performance predictions are reviewed for installations proposed for the AMST YC-14 and the KC-135 airplanes. The other major area of aerodynamic interference discussed is that of engine nacelle installations. Slipper and overwing nacelles have received much attention because of their potential for noise reduction, propulsive lift and improved ground clearance. A major challenge is the integration of such nacelles with the supercritical flow on the upper surface of a swept wing in cruise at high subsonic speeds.
    Keywords: AERODYNAMICS
    Type: AGARD Subsonic(Transonic Configuration Aerodyn.; 19 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Publication Date: 2017-10-02
    Description: Basic concepts of finite difference solution techniques for unsteady transonic flows are presented. The hierarchy of mathematical forumulations that approximate the Navier-Stokes equations are reviewed. The basic concepts involved in constructing numerical algorthms to solve these formulations are given. Semi-implicit and implicit schemes are constructed and analyzed. The discussion focuses primarily on techniques for solving the low frequency transonic small disturbance equation. This is the simplest formulation that contains the essence of inviscid unsteady transonic flow physics. The low frequency formulation is emphasized here because codes based on this theory can be run in minutes of processor time on currently available computers. Furthermore, numerical techniques involved in solving this simple formulation also apply to the more complicated formulations. Extensions to these formulations are briefly described. An indication of the present capability for solving unsteady transonic flows is provided. Important areas of future research for the advancement of computational unsteady transonic aerodynamics are described.
    Keywords: AERODYNAMICS
    Type: AGARD Spec. Course on Unsteady Aerodyn.; 24 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...