Modelling an upend hinge in hydrodynamic simulations of a monopile upend operation

The offshore wind energy industry is quite literally reaching for the sky to meet the increasing demand for renewable energy in Europe. Offshore wind turbines are sprouting out of the waves off the coast of many European nations and their size is increasing rapidly. As the turbines become larger and the waters in which they are placed become...

A general substructure-based framework for input-state estimation using limited output measurements

This paper presents a general framework for estimating the state and unknown inputs at the level of a system subdomain using a limited number of output measurements, enabling thus the component-based vibration monitoring or control and providing a novel approach to model updating and hybrid testing applications. Under the premise that the...

Effect of instrumentation position and direction inaccuracy on the calculation of virtual point transformed FRFs

This work comprises research in the field of Experimental Dynamics. This technique is currently used in the automotive area and is used to enhances the current state of FEM with the inclusive of test- based models. Building test-based models for EDS (Experimental Dynamic Substructuring) requires very accurate measurement, and this thesis...

Improving Inverse Substructuring

The electrification of drive trains in current and next generation vehicles require vibration dampers that possess different dynamic properties than its internal combustion engine counterparts. This makes research in automotive vibration damping a hot topic. Research in this field often contains the practice of Frequency Based Substructuring ...

Dynamic Substructuring for Efficient Vibrational Studies in Buildings

As a reaction to urban densication, light weight building is an attractive concept for optimally utilizing the capacity of the existing built environment. A common issue paired with light weight construction is the need to engage in vibrational design, in order to minimize hindrance due to human activities such as walking, that cause vibrations...

System equivalent model mixing

This paper introduces SEMM: a method based on Frequency Based Substructuring (FBS) techniques that enables the construction of hybrid dynamic models. With System Equivalent Model Mixing (SEMM) frequency based models, either of numerical or experimental nature, can be mixed to form a hybrid model. This model follows the dynamic behaviour of a...

Experimental dynamic substructuring: Analysis and design strategies for vehicle development

Sound and vibration have a defining influence on our perception of product quality. They are especially well-known aspects in the automotive industry; a branch which sees, besides safety and driving comfort, ever-increasing expectations of the acoustic experience. After all, a smooth and silent driving experience appeals to a feeling of <i...

General framework for transfer path analysis: History, theory and classification of techniques

Transfer Path Analysis (TPA) designates the family of test-based methodologies to study the transmission of mechanical vibrations. Since the first adaptation of electric network analogies in the field of mechanical engineering a century ago, a multitude of TPA methods have emerged and found their way into industrial development processes....

Coupled Simulations of Wind Turbines and Offshore Support Structures: Strategies based on the Dynamic Substructuring Paradigm

Large scale offshore wind power has been recognized as a key technology to increase the share of renewable energy. However, as this energy source is currently still relatively expensive, efforts are made to significantly reduce its costs. Cost reductions are to be achieved, for instance, by installing larger turbines in larger offshore wind...

Experimental dynamic substructuring using direct time-domain deconvolved impulse response functions

The dynamics of systems can be analysed by combining the dynamics of its components. This method is generally know as dynamic substructuring. It allows for efficient computation of the dynamics of structures that would otherwise be to complex to determine. Most dynamic substructuring approaches use the frequency domain for the re-assembling of...

Machines with high accuracy on factory floors

This thesis will propose a new method to predict the response of sensitive equipment, once it is installed on the factory floor. Currently, only the stiffness of the floor is taken into account when the dynamic response of a machine on a floor is predicted. To improve these methods, a short literature survey is done about the dynamics of factory...

Identification of damping in joints using dynamic substructuring techniques

Predicting and characterizing damping in joints and connections is a bottleneck in many design processes. New analysis techniques can be used to advance the engineering practice. These techniques would for example be useful to make a better estimation of the coupled dynamics of an engine-generator set (gen-set) on a ship. Large ships are...

Dynamic response characterization of complex systems through operational identification and dynamic substructuring- An application to gear noise propagation in the automotive industry

This thesis deals with new methods, which can determine the dynamic response of a complex system identified in operation, based on the knowledge of its subsystem dynamics and excitation. In the first part of this thesis, the identification of component excitation and its transmission into the total system will be addressed. The identification of...