Zobrazeno 1 - 10
of 92
pro vyhledávání: '"Aviv Rosen"'
Autor:
Jacob Enciu, Aviv Rosen
Publikováno v:
Journal of the American Helicopter Society. 62:1-13
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e46f8451756bd29d53fb4962e39c6f68
https://doi.org/10.4050/jahs.62.012007
https://doi.org/10.4050/jahs.62.012007
Publikováno v:
Journal of the American Helicopter Society. 60:1-13
The stabilization of “difficult” loads that become aerodynamically unstable at airspeeds well below the power-limited speed of the helicopter-load configuration has been studied since the 1960s. This paper looks at the possibility of stabilizing
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7f1c245c26c83439749feb9d228c41d9
https://doi.org/10.4050/jahs.60.042006
https://doi.org/10.4050/jahs.60.042006
Autor:
Aviv Rosen, K. Enciu
Publikováno v:
The Aeronautical Journal. 119:1073-1103
Box-like slung loads exhibit periodic yaw response instabilities, while carried externally by a helicopter. When coupled with the slung load longitudinal and lateral pendulum motions, these instabilities result in significant pendulum oscillations of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cf9bc6cf904e8a00f3dfc372f026e464
https://doi.org/10.1017/s0001924000011143
https://doi.org/10.1017/s0001924000011143
Autor:
K. Enciu, Aviv Rosen
Publikováno v:
AIAA Journal. 53:723-738
The maximum safe speed of a helicopter carrying an underslung load is frequently limited due to load instability problems. Rear-mounted fins were previously demonstrated as an efficient means for stabilization of a problematic load. Past stability an
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7f676e25f34a202d2be8c16403fb25c1
https://doi.org/10.2514/1.j053241
https://doi.org/10.2514/1.j053241
Publikováno v:
Journal of the American Helicopter Society. 59:1-12
The first new load is the TRIO container that can be flown in three configurations with different heights. The second new load is a ribbon bridge interior bay section. Wind tunnel results with models of the new loads exhibit in general good agreement
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7748ca3938d03d505a16f9891c3395cf
https://doi.org/10.4050/jahs.59.042004
https://doi.org/10.4050/jahs.59.042004
Publikováno v:
Journal of the American Helicopter Society. 59:1-12
Previously, the authors showed that dynamic wind tunnel tests of a suspended CONEX cargo container model exhibited encouraging levels of success in predicting the stability characteristics and speed envelope of the full-scale load. The present study
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9e7dece5c174510d70d88b068209604c
https://doi.org/10.4050/jahs.59.042003
https://doi.org/10.4050/jahs.59.042003
Autor:
D. Seter, Aviv Rosen
Publikováno v:
Journal of Aircraft. 51:236-248
Autorotation in a steady-state axial motion is investigated theoretically and experimentally. A simplified model presents the major physical parameters affecting this phenomenon, giving an insight into the phenomenon and the influence of various para
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::233c9979d93de134ac0fd8d61c11923c
https://doi.org/10.2514/1.c032305
https://doi.org/10.2514/1.c032305
Autor:
Sivan Kominer, Aviv Rosen
Publikováno v:
AIAA Journal. 51:1382-1393
In a previous paper, a novel approach to axisymmetric actuator-disk modeling was presented. In the present paper, this modeling is extended to include the case of a skewed flow, which is asymmetric. Similar to the axisymmetric case, it is assumed tha
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::8eed63db9a367feb507b696f87c7b253
https://doi.org/10.2514/1.j052057
https://doi.org/10.2514/1.j052057
Autor:
V. Ognev, Aviv Rosen
Publikováno v:
Journal of Aircraft. 48:1708-1721
The influence of various unsteady aerodynamic models on the flutter prediction of propellers in axial flight is investigated. The aerodynamic models include: Theodorsen’s model, two different cascade models, and a detailed three-dimensionalmodel.Am
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2e8893427b448d5a439b0ac7a8c4d68b
https://doi.org/10.2514/1.c031357
https://doi.org/10.2514/1.c031357
Autor:
K. Enciu, Aviv Rosen
Publikováno v:
Journal of Aircraft. 48:952-962
A six-degree-of-freedom simulation of helicopter roll on takeoff is used for evaluation of a twin-engine helicopter continued takeoff trajectory, following one engine failure. For this study, an AH-64A Apache was used. The simulation is used for the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::68574f778612cd0c4733decc93dce0ce
https://doi.org/10.2514/1.c031183
https://doi.org/10.2514/1.c031183