ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 0168-9002
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0920-5632
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract  A novel optical diagnostic technique, dual hologram shearing interferometry, for measuring density gradients of different phase objects is proposed and demonstrated. The lateral shearing is achieved by using a phase grating. A holographic interferometer has been developed and designed on the base of a single pass Z type conventional schlieren device. The interferometer’s scheme is insensitive to acoustical disturbances, similarly to the conventional schlieren layout, and is capable of recording holograms with a continuous wave laser during the wind tunnel run. The features of the technique make it tolerant to both the temporal coherence of the laser light source and to the relatively low, schlieren quality optical windows of the wind tunnel’s test section. The obtained reconstructed lateral shearing interferograms with a large region of overlap have high contrast and may have an arbitrary orientation and/or spacing of the background interference fringes. It is believed that the proposed approach will become a useful tool for visualization and accurate mapping of the density gradients of gas dynamic flow fields, in wind and shock tunnels, where acoustic noise problems may dramatically affect reference beam holographic schemes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract  A novel optical diagnostic approach, namely, a dual hologram shearing interferometry with enhanced sensitivity, is proposed for visualization, and for measuring the density gradients of the flow in wind tunnels. The technique is especially useful for strong turbulent and/or unsteady regions flows. The features of the technique make it tolerant to vibrational disturbances typical to many wind tunnel facilities. The method was demonstrated by its application to a supersonic flow over a spherically blunted nose cone/cylinder model.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Experiments in fluids 14 (1993), S. 241-245 
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A study of the flow field in a 2 D arrangement of fins was carried out by means of flow visualization in a vertical water tunnel. A similar arrangement of fins had been tested as a conceptual heat sink, and the heat transfer measurement showed a dependence of the heat transfer qualities on the geometrical parameters of the fin's array. The current study examines the complex flow field structure in order to obtain a better understanding of the convection process. The model is built of several series of fins, generating a multi-cell structure. The investigation included a systematic variation of the fins' chord and inclination angle, as well as the flow velocity. Two main flow structures were observed. In the first one, the flow separates from the leading edge of each fin. Due to the influence of its neighbouring fins, the flow re-attaches to the fin, creating a closed separation zone. A vortex fills this separation zone. The main flow accelerates in the passage that is created between the separation bubble and the neighbouring fin. In the second flow structure, the flow separates from both leading and trailing edges of each fin. The separation is in alternating order and generates a nonsteady pair of vortices. This separation pattern is similar to that of a single plate at high angle of attack, and the effect of the neighbouring fins is only to narrow the wake. The pressure drop across the model was measured and correlated to a single nondimensional variable on a single curve.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Experiments in fluids 3 (1985), S. 209-214 
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A modified and improved system for the measurement of Magnus loads on spinning models, at various spin rates and at various angles of attack is presented. The objective of the modifications was to increase the measuring-system sensitivity to the Magnus loads, while increasing its stiffness relative to the other loads. The spin mechanism was designed to minimize interference with the outer flow. The system was designed to operate in conjunction with any standard balance (of the appropriate diameter), so that it could be used at all wind-tunnel speeds, from low subsonic to supersonic. The versatility of the new system was demonstrated in successful measurements at various Mach numbers. Test Mach numbers varied from M = 0.025 to M = 0.4, with spin rates from zero to 30,000 rpm, and angles of attack from α = 0° to α = 90°. The test results show that Magnus loads can be measured accurately, both at low and high angles of attack and spin rates.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Experiments in fluids 7 (1989), S. 56-60 
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A new approach to the measurement of the axial force is presented. A non-integral axial-force measuring element, housed within the wind-tunnel model, avoids the interactions that are caused by nonlinear elastic phenomena characteristic of integral balances. The new design overcomes other problems, such as friction, misalignment and relative motion between metric elements, that plagued previous attempts at separate measurement of the axial force. Calibration and test results prove the ability of the new approach to duplicate and even surpass the results of much more complicated and expensive integral balances. The advantages of the new design make it the best known solution for particular measurement problems.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Conventional interferometric measurements of weak phase objects run into serious accuracy problems due to low sensitivity and/or optical aberrations. This paper describes an optical method, based on the dual hologram technique, with enhanced sensitivity and with compensating for the optical aberrations. It provides a reliable acquisition of the phase information from wide range of weak phase objects including high speed flow fields. The method was demonstrated by mapping the density field of a small size axisymmetric supersonic jet as a representative weak phase object.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Experiments in fluids 7 (1989), S. 566-568 
    ISSN: 1432-1114
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Conclusion The use of a smooth surface, for small projectiles, may lead to a reduction of drag at zero angle of attack. However, for specific configurations, especially those with blunt aft sections, an adverse normal force characteristic may develop, causing stability problems, similar to the one described by Schneider (1978). On the other hand, a skilful use of the separation-zone motion could serve as a maneuvering tool for unguided projectiles that are required to perform a search motion, and a built-in instability could maintain the desired motion.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-2242
    Keywords: Amount of phenotypic plasticity ; Pattern of phenotypic plasticity ; Genotype X environment interaction ; Inbreeding depression ; Phlox drummondii
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Inbreeding is known to increase developmental instability in outbreeding plants, and it has been argued that phenotypic plasticity in response to environmental variation might be similarly affected. To investigate whether phenotypic plasticity is altered by inbreeding, an outcrossed group and three successive generations of inbred cultivated Phlox drummondii were grown in six different treatments (Control, Low Water, Low Nutrient, Early and Late Leaf Removal, and Small Pots). Twelve plant characters were measured to determine the effects of the treatments and inbreeding. For those characters where inbreeding level by treatment interaction was indicated, the amounts and patterns of plasticity were examined to determine the source of the interaction. Despite substantial evidence for inbreeding depression of plant vigor and fecundity, there was no indication of an increase in the amount of phenotypic plasticity with progressive inbreeding. There was also no evidence that inbreeding systematically disrupts the pattern of plastic response to the environment.
    Type of Medium: Electronic Resource
    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...