A holistic approach to predict, measure and reduce environmental pressures of polymetallic nodule collection

There is an expected increase in demand of critical raw materials, e.g. nickel and cobalt, mainly driven by the shift towards renewable energy solutions and the increase in production of electric vehicles. That trend has raised the interests for the mining of polymetallic nodules. The most extensive nodule depostions are found on the abyssal...

Numerical and Experimental Study of Acoustic Emission Source Signal Reconstruction in Fibre-Reinforced Composite Panels

The recording and processing of acoustic emissions can be used to identify and localise damage mechanisms occurring in engineering structures. In plate-like structures, acoustic emissions propagate through the structure as guided waves. With a measurement location away from the source location, dispersion effects in the guided wave distort...

Descriptive Statistical Analysis of Frequency control-related variables of Nordic Power System

This paper presents a descriptive statistical analysis (DSA) of time-series of electro-mechanical quantities related to the frequency control (e.g. kinetic energy (KE), electrical frequency and power demand) of the Nordic power system (NPS). The idea of the DSA is to identify main observables features and patterns between these variables....

Solid State Diffusion Bonding of ODS Eurofer Steel by Spark Plasma Sintering

Oxide dispersion strengthened (ODS) steels are considered to be one of the candidate structural materials for advanced nuclear applications due to their high elevated-temperature strength, corrosion resistance, and radiation tolerance. Joining of ODS steels by traditional fusion joining techniques is not applicable, because the melting...

The Effect of Stress Wave Dispersion on the Drivability Analysis of Large-Diameter Monopiles

Due to the increasing need for energy from renewable resources, a large number of offshore wind farms are planned to be constructed in the near future. Despite the plethora of available foundation concepts for offshore wind turbines, the monopile foundation is the most widely adopted concept in practice. To predict the installation process for a...

Identification and Treatment of Erodible Clays in Dikes

When it comes to flood protection, the established method is to use impermeable material in dikes, to prevent seepage. This material is usually some kind of clay soil which is considered as impermeable and erosion-resistant. Dispite that, in many occasions not only seepage, but the failure of the dam occured due to surface erosion, because these...

Damage resistance of dispersed-ply laminates

This paper presents the design procedure of a quasi-isotropic (QI) laminate employing dispersion of ply orientations. The goal is to improve damage resistance of a laminate under low velocity impact (LVI). The LVI is treated as a quasi-static loading and instead of a plate a laminated beam is considered. Therefore, this situation simplifies the...

A Symmetry and Dispersion-Relation Preserving High-Order Scheme for Aeroacoustics and Aerodynamics

A new high-order, finite-volume scheme is presented that preserves the symmetry property and the dispersion relation of the convective operator. The scheme is applied to large-eddy simulation of compressible, turbulent flow and to the solution of the linearized Euler equations for aeroacoustic applications. For large-eddy simulation, the...

An overview of numerical methods for acoustic wave propagation

This paper presents a short overview of recent developments of low-dispersive and low-dissipation finite-difference schemes as an alternative to more classical methods of applied mathematics. Needs of accurate and efficient numerical solvers in computational aeroacoustics have motivated these developements over the last two decades. Properties...

Numerical study of aerosol dust behaviour in aspiration bunker

The information concerning dispersed composition and concentration of dust particles which are caught by local exhausts is necessary for scientific proved choice of dust retaining devices. To receive this information it is necessary to apply the stochastic [1] and determinate methods [2]. The last ones are based on the studying of single dust...

Numerical study for accidental gas releases from high pressure pipelines

This work concerns the analysis of consequences of gas releases from high pressure pipelines due to accidental events. This analysis has been performed using the CFD code Fluent. The first step of the work intended to evaluate the capability of Fluent to adequately simulate a supersonic underexpanded free jet. This validation has been based on...

Numerical Dispersion of Gravity Waves

In this work numerical dispersion relations for atmospheric gravity waves are experimentally analyzed using the anelastic mesoscale model METRAS. The dependency of the group velocity on grid size and advection scheme (central scheme (CDF) and methods based on the essentially non-oscillatory (ENO) method) is presented showing a retardation of the...

Correction of the phase retardation caused by intrinsic birefringence in deep UV lithography

In the year 2001 it was reported that the birefringence induced by spatial dispersion (BISD), sometimes also called intrinsic birefringence, had been measured and calculated for fluorides CaF2 and BaF2 in the deep UV range. It was also shown that the magnitude of the BISD in these cubic crystals is sufficiently large to cause serious problems...

Hydraulic fracture characterization with dispersion measurements of seismic waves

Experimental verification of stress-induced anisotropy

Image analysis of surf zone hydrodynamics