Efficient numerical representation of the impacts of flexible plant reconfiguration on canopy posture and hydrodynamic drag

Abstract Fatigue crack growth can occur in elastomeric structures whenever cyclic loading is applied. In order to design robust products, sensitivity to fatigue crack growth must be investigated and minimized. The task has two basic components: (1) to define the material behavior through measurements showing how the crack growth rate depends on conditions that drive the crack, and (2) to compute the conditions experienced by the crack. Important features relevant to the analysis of structures include time-dependent aspects of rubber’s stress-strain behavior (as recently demonstrated via the dwell period effect observed by Harbour et al.), and strain induced crystallization. For the numerical representation, classical fracture mechanical concepts are reviewed and the novel material force approach is introduced. With the material force approach at hand, even dissipative effects of elastomeric materials can be investigated. These complex properties of fatigue crack behavior are illustrated in the context of tire durability simulations as an important field of application.

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OUTDOOR TESTS OF A TOWED BOAT MODEL WITH FUEL COMBUSTION IN A BOTTOM CAVITY

NONEQUILIBRIUM PROCESSES: RECENT ACCOMPLISHMENTS ◽

10.30826/nepcap9a-45 ◽

2020 ◽

Author(s):

S. M. FROLOV ◽

◽

S. V. Platonov ◽

K. A. AVDEEV ◽

V. S. AKSENOV ◽

...

Keyword(s):

Drag Force ◽

Direct Contact ◽

Propulsion System ◽

Hydrodynamic Drag ◽

Atmospheric Air ◽

System A ◽

Bottom Cavity ◽

Gas Cavity ◽

System Power ◽

Gas Supply

To reduce the hydrodynamic drag force to the movement of the boat, an artificial gas cavity is organized under its bottom. Such a cavity partially insulates the bottom from direct contact with water and provides “gas lubrication” by means of forced supply of atmospheric air or exhaust gases from the main propulsion system. A proper longitudinal and transverse shaping of the gas cavity can significantly (by 20%-30%) reduce the hydrodynamic drag of the boat at low (less than 3%) consumption of the propulsion system power for gas supply.

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On the Positivity of $\mathbf{{a}}$-Linear with Random Finitely

10.31219/osf.io/7j42h ◽

2020 ◽

Author(s):

Amanda Bolton

Keyword(s):

Representation Theory ◽

Central Problem ◽

Numerical Representation

Let $\rho$ be an ultra-unique, reducible topos equipped with a minimal homeomorphism. We wish to extend the results of \cite{cite:0} to trivially Cartan classes. We show that $d$ is comparable to $\mathcal{{M}}$. This leaves open the question of uniqueness. Moreover, a central problem in numerical representation theory is the description of irreducible, orthogonal, hyper-unique graphs.

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Time and Frequency Domain Dynamic Analysis of Offshore Mooring

Journal of Marine Science and Engineering ◽

10.3390/jmse9070781 ◽

2021 ◽

Vol 9 (7) ◽

pp. 781

Author(s):

Shi He ◽

Aijun Wang

Keyword(s):

Dynamic Analysis ◽

Frequency Domain ◽

Time Domain ◽

Linearization Method ◽

Euler Method ◽

Single Component ◽

Hydrodynamic Drag ◽

Lumped Mass ◽

Mooring Lines ◽

The Time Domain

The numerical procedures for dynamic analysis of mooring lines in the time domain and frequency domain were developed in this work. The lumped mass method was used to model the mooring lines. In the time domain dynamic analysis, the modified Euler method was used to solve the motion equation of mooring lines. The dynamic analyses of mooring lines under horizontal, vertical, and combined harmonic excitations were carried out. The cases of single-component and multicomponent mooring lines under these excitations were studied, respectively. The case considering the seabed contact was also included. The program was validated by comparing with the results from commercial software, Orcaflex. For the frequency domain dynamic analysis, an improved frame invariant stochastic linearization method was applied to the nonlinear hydrodynamic drag term. The cases of single-component and multicomponent mooring lines were studied. The comparison of results shows that frequency domain results agree well with nonlinear time domain results.

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