Numerical Simulation of Dynamic Response of PC-Type HgCdTe Detector Irradiated by in-Band and Out-of-Band Laser Beams

A 7.8m/s vertical drop simulate of a full composite fuselage section was conducted with energy-absorbing floor to evaluate the crashworthiness features of the fuselage section and to predict its dynamic response to dummies in future. The 1.52m diameter fuselage section consists of a high strength upper fuselage frame, one stiff structural floor and an energy-absorbing subfloor constructed of Rohacell foam blocks. The experimental data from literature [6] were analyzed and correlated with predictions from an impact simulation developed using the nonlinear explicit transient dynamic computer code MSC.Dytran. The simulated average acceleration did not exceed 13g, by contrast with experimental results, whose relative error is less than 11%. The numerical simulation results agree with experiments well.

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Dynamic Test of Bird Strike on a Flat Plate Made from LY-12 Aluminium

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.765-767.3158 ◽

2013 ◽

Vol 765-767 ◽

pp. 3158-3161

Author(s):

Jun Liu ◽

Zheng Li Zhang

Keyword(s):

Numerical Simulation ◽

Dynamic Response ◽

Dynamic Test ◽

Time History ◽

Aircraft Design ◽

Bird Strike ◽

Test Results ◽

Valuable Data ◽

Good Agreement ◽

Peak Value

Tests of bird strike have been carried out on plate made from LY-12 Aluminium. The test was down with the projectile impacting the target perpendicularly at velocity of 40m/s, 80m/s, 120m/s respectively. The displacement-time history curves and strain-time history curves of on LY-12 Aluminium plate were measured. The good agreement of the results between two specimens in one group indicated that the results tested in the presnet paper are reliable. The dynamic response of the plate and damage modes of the bird influenced by striking velocity were analyzed. The peak value of the displacement linear enlarged with the increasing of the striking velocity. The test results in the present paper provided valuable data for aircraft design impacted by bird, and also provided abundant test datas for the numerical simulation model applied in bird striking.

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Dynamic Response of a Spar-Type Floating Wind Turbine at Power Generation

Volume 7: Ocean Space Utilization; Professor Emeritus J. Randolph Paulling Honoring Symposium on Ocean Technology ◽

10.1115/omae2014-24693 ◽

2014 ◽

Cited By ~ 6

Author(s):

Tomoaki Utsunomiya ◽

Shigeo Yoshida ◽

Soichiro Kiyoki ◽

Iku Sato ◽

Shigesuke Ishida

Keyword(s):

Numerical Simulation ◽

Power Generation ◽

Dynamic Response ◽

Wind Turbine ◽

Prestressed Concrete ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Floating Foundation ◽

Mooring Dynamics ◽

Nagasaki Prefecture

In this paper, dynamic response of a Floating Offshore Wind Turbine (FOWT) with spar-type floating foundation at power generation is presented. The FOWT mounts a 100kW wind turbine of down-wind type, with the rotor’s diameter of 22m and a hub-height of 23.3m. The floating foundation consists of PC-steel hybrid spar. The upper part is made of steel whereas the lower part made of prestressed concrete segments. The FOWT was installed at the site about 1km offshore from Kabashima Island, Goto city, Nagasaki prefecture on June 11th, 2012. Since then, the field measurement had been made until its removal in June 2013. In this paper, the dynamic behavior during the power generation is presented, where the comparison with the numerical simulation by aero-hydro-servo-mooring dynamics coupled program is made.

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Topological Charge and Asymptotic Phase Invariants of Vortex Laser Beams

Photonics ◽

10.3390/photonics8100445 ◽

2021 ◽

Vol 8 (10) ◽

pp. 445

Author(s):

Alexey A. Kovalev ◽

Victor V. Kotlyar ◽

Anton G. Nalimov

Keyword(s):

Numerical Simulation ◽

Data Transmission ◽

Topological Charge ◽

Light Field ◽

Observation Point ◽

Laser Beams ◽

Optical Data ◽

Optical Signals ◽

Asymptotic Phase ◽

Ring Approximation

It is well known that the orbital angular momentum (OAM) of a light field is conserved on propagation. In this work, in contrast to the OAM, we analytically study conservation of the topological charge (TC), which is often confused with OAM, but has quite different physical meaning. To this end, we propose a huge-ring approximation of the Huygens–Fresnel principle, when the observation point is located on an infinite-radius ring. Based on this approximation, our proof of TC conservation reveals that there exist other quantities that are also propagation-invariant, and the number of these invariants is theoretically infinite. Numerical simulation confirms the conservation of two such invariants for two light fields. The results of this work can find applications in optical data transmission to identify optical signals.

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