A two-scale FE model to address connections in coupled fire-structure simulations

A two-scale finite element model is proposed to improve two-way coupled fire-structure simulations. The model consists of (i) a global-scale model, which accounts for the structure, and (ii) a small-scale model for each connection. Structural parts on the global scale are connected by spring elements, which stiffness properties are updated by...

The Role of Molding Compound Microstructure for Packaging Reliability

Molding compounds are key materials to deliver well packaged reliable IC’s for demanding applications, such as automotive electronics. With shrinking sizes of IC’s and the increased requirements with respect to loading conditions, application environment and lifetime, the reliability of the packaging becomes increasingly important. The...

A mesoscale modelling perspective of cracking process and fracture energy under high strain rate tension

This paper presents a numerical modelling study on the simulation of the cracking process and fracture energy in concrete under high strain rate. To capture the stress wave effect and the damage evolution at the meso-length scale, both a homogeneous model with a millimetre-resolution mesh and an explicit heterogeneous mesoscale model with random...

A barrier for low frequency noise from starting aircraft: Comparison between numerical and scale model results

Amsterdam Airport Schiphol has organized a competition to design a noise mitigating measure along the 'Polderbaan' runway. Its main goal is to reduce the low frequency (LF) ground noise from starting aircraft. The winning concept is a flexible parabolic shaped noise barrier positioned relatively close to the runway. There is a large distance...

Efficient extraction of thin-film thermal parameters from numerical models via parametric model order reduction

In this paper we present a novel highly efficient approach to determine material properties from measurement results. We apply our method to thermal properties of thin-film multilayers with three different materials, amorphous silicon, silicon nitride and silicon oxide. The individual material properties are identified by solving an optimization...

Elimination of flow-induced pulsations and vibrations in a process installation: a combination of on site measurements, calculations and scale modeling

The aim of the work described in this paper was to trace and eliminate vibration sources in a low pressure system with high flow velocities. Considerable vibration on the pipe system between a flashing vessel (6.5 m diameter) and heat-exchangers resulted in fatigue failure, leakage and subsequent shut down of a chemical production plant. As...

Inverse modeling of groundwater flow using model reduction

Numerical groundwater flow models often have a very high number of model cells (greater than a million). Such models are computationally very demanding, which is disadvantageous for inverse modeling. This paper describes a low-dimensional formulation for groundwater flow that reduces the computational burden necessary for inverse modeling. The...

Unidimensionality and reliability under Mokken scaling of the Dutch language version of the SF-36

The sub-scales of the SF-36 in the Dutch National Study are investigated with respect to unidimensionality and reliability. It is argued that these properties deserve separate treatment. For unidimensionality we use a non-parametric model from item response theory, called the Mokken scaling model, and compute the corresponding scalability...

A modified RRSQRT-filter for assimilating data in atmospheric chemistry models

The RRSQRT-filter is a special formulation of the Kalman filter for assimilation of data in large scale models. In this formulation, the covariance matrix of the model state is expressed in a limited number of modes. Two modifications have been made to the filter such that it is more robust when applied in combination with an atmospheric...

Budget calculations for ozone and its precursors: Seasonal and episodic features based on model simulations

Results from two air quality models (LOTOS, EURAD) have been used to analyse the contribution of the different terms in the continuity equation to the budget of ozone, NO(x) and PAN. Both models cover large parts of Europe and describe the processes relevant for tropospheric chemistry and dynamics. One of the models is designed to simulate...

Measuring TGV source strength with Syntacan

A 10 m high, vertical, synthetic acoustic antenna (Syntacan) has been used to measure the acoustic source strength and the vertical source distribution of a French TGV, as a function of the speed of the train, the frequency of the sound and the coach type (passenger coach, power car). The results are intended as input for calculation schemes and...