| 1. |
- Abata, E., et al.
(författare)
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Study of energy response and resolution of the ATLAS barrel calorimeter to hadrons of energies from 20 to 350 GeV
- 2010
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576 .- 0167-5087. ; 621:1-3, s. 134-150
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Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. In this paper, the results of the measurements of the response of the barrel calorimeter to hadrons with energies in the range 20-350 GeV and beam impact points and angles corresponding to pseudo-rapidity values in the range 0.2-0.65 are reported. The results are compared to the predictions of a simulation program using the Geant 4 toolkit. (C) 2010 Published by Elsevier B.V.
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| 2. |
- Quaranta, Giuseppe, et al.
(författare)
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Aeroelastic Analysis of a Cycloidal Rotor Under Various Operating Conditions
- 2018
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Ingår i: Journal of Aircraft. - 0021-8669 .- 1533-3868. ; 55:4, s. 1675-1688
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Tidskriftsartikel (refereegranskat)abstract
- The aeroelasticity of a cycloidal rotor in forward flight is investigated using an analytical and a numerical model; the latter is based on a multibody dynamics approach. Three experimental sources are used to validate the multibody model. The influence of the number of blades, their stiffnesses, and their skin thicknesses are investigated. At high pitch angles, before stall and flexibility effects occur, increasing the number of blades produces more thrust for the same power. Flexibility and skin thickness considerably affect the required pivot rod strength and blade deformation. Simply supported blades exhibit severe deformations when compared to clamped blades. Thrust and power are both influenced in a similar and moderate way by flexibility. The rotor response to wind gusts is also analyzed. The angular velocity of the rotor significantly affects the response of the rotor to wind gusts. The direction of the gusting wind has an important influence on power, whereas thrust increases regardless of wind direction. Finally, the rotor response lags minimally behind the arrival of the gust.
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| 3. |
- Xisto, Carlos, 1984, et al.
(författare)
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Parametric Analysis of a Large-scale Cycloidal Rotor in Hovering Conditions
- 2017
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Ingår i: Journal of Aerospace Engineering. - 1943-5525 .- 0893-1321. ; 30:1, s. 04016066-04016066-14-
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Tidskriftsartikel (refereegranskat)abstract
- In this work, four key design parameters of cycloidal rotors, namely the airfoil section; the number of blades; the chord-to-radius ratio; and the pitching axis location, are addressed. The four parameters, which have a strong effect on the rotor aerodynamic efficiency are analyzed with an analytical model and a numerical approach. The numerical method is based on a finite-volume discretization of two-dimensional Unsteady Reynolds Averaged Navier-Stokes equations on a multiple sliding mesh, are proposed and validated against experimental data. A parametric analysis is then carried out considering a large-scale cyclogyro, suitable for payloads above 100 kg, in hovering conditions. Results demonstrate that the airfoil thickness significantly affects the rotor performance; such a result is partly in contrast with previous findings for small- and micro-scale configurations. Moreover, it will be shown that increasing the number of blades could result in a decrease of the rotor efficiency. The effect of chord-to-radius will demonstrate that values of around 0.5 result in higher efficiency. Finally it is found out that for these large systems, in contrast with micro-scale cyclogyros, the generated thrust increases as the pitching axis is located away from the leading edge, up to 35% of chord length. Further the shortcomings of using simplified analytical tools in the prediction of thrust and power in non-ideal flow conditions will be highlighted and discussed.
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