Tapering of the interventricular septum can affect ultrasound shear wave elastography: An in vitro and in silico study

Shear wave elastography (SWE) has the potential to determine cardiac tissue stiffness from non-invasive shear wave speed measurements, important, e.g., for predicting heart failure. Previous studies showed that waves traveling in the interventricular septum (IVS) may display Lamb-like dispersive behaviour, introducing a thickness-frequency...

An experimental and numerical investigation of sphere impact on alumina ceramic

In this study, the impact of a steel spherical projectile on an alumina ceramic is considered. New experimental and numerical results are presented and analysed. Numerical results are obtained using the Finite Element Method and the upgraded viscosity regularized Johnson-Holmquist-2 constitutive model to describe the ceramic material behaviour....

Numerical modeling of alumpedacoustic source actuated by a piezoelectric stack device that is driven by a switching amplifier

This paper studies an acoustic source with a relatively small thickness and high bending stiffness. Piezoelectric actuators are used to drive the moving component of the acoustic source. In the current study, a lumped model is used to represent the acoustic source that is excited by a piezoelectric stacked actuator. The equivalent electrical...

Wrinkling, fracture, and necking: The various failure modes in maritime crash

Depending on the state of stress, material can fait in a number of different modes during a collision. Three modes are identified here as material separation in the absence of necking, material separation after the onset of necking, and localized buckling/wrinkling. Through a series of case studies, the states of stress present in a collision...

Impact resistance cryogenic bunker fuel tanks

The increasing use of liquefied natural gas (LNG) as bunker fuel in ships, calls for an elaborate study regarding the risks involved. One particular issue is the vulnerability of cryogenic LNG storage tanks with respect to impact loadings, such as ship collisions and dropped objects. This requires an understanding of the impact resistance of the...

Estimation of failure parameters for finite element simulations based on a single state of stress and arbitrary stress-strain relation

Crash analysis in the maritime and offshore industry typically relies on failure criteria that are based only on uniaxial states of stress. However, it is well known that the failure strain depends on the state of stress, and the state of stress in ship collisions is not necessarily uniaxial. Although more detailed failure models are routine in...

Measurement of Seebeck coefficient of electroplated thermoelectric films in presence of a seed layer

Effect of the seed layer on Seebeck coefficient measurement of electroplated thermoelectric films was quantitatively analyzed. It is found that sheet, rather than bulk resistance of the seed layer, or more precisely its relative comparison to sheet resistance of the film, determines the effects. The analysis reveals that the seed layer's effect...

Experimental and numerical study of friction and braking characteristics of rolling tires

Throughout the tire industry, virtual testing has been widely adopted in the design process. Both static deformation and dynamic response of the tire rolling on the road must be accurately predicted to evaluate the handling performance of a tire. Unfortunately, experimental characterization of rubber compound frictional properties is limited,...

Conductive plastic film electrodes for Pulsed Electric Field (PEF) treatment: A proof of principle

Nowadays Pulsed Electric Field (PEF) treatment of food needs to be performed prior to packaging, either hygienic or aseptic packaging is necessary. New techniques for PEF treatment after packaging can be considered when plastic conductive (film) electrodes can be integrated within the package, so that the package and the product can be treated...

Characterization of epitaxial Pb(Zr,Ti)O3 thin films deposited by pulsed laser deposition on silicon cantilevers

This paper reports on the piezoelectric-microelectromechanical system micro-fabrication process and the behavior of piezoelectric stacks actuated silicon cantilevers. All oxide layers in the piezoelectric stacks, such as buffer-layer/bottom-electrode/film/top-electrode: YSZ/SrRuO\3/Pb(Zr, Ti)\3/SrRuO\3, were grown epitaxially on the Si template...

Finite element simulations and experiments to determine the residual damage of a CFRP composite material after ballistic impacts

The use of lightweight systems is essential for future combat systems. More and more steel structures are replaced by composite structures. This also influences the vulnerability of the platform. A finite element material model is created in Autodyn of the carbon fiber reinforced plastic (CFRP) AS4/3501 in order to predict both the residual...