Annual Report Department

3.10Applied combustion

3.10.1Bilateral project with Indaver: Measurements in municipal and industrial waste burning facilities

Partners: Indaver, K.U. Leuven - TME

Objective: To map the internal temperature distribution in medium scaled furnaces with water-cooled suction pyrometer.

Period: Mar 2003 & Dec 2003

Contact: E. Van den Bulck, K. Vanoverberghe

3.10.2Bilateral project with Indaver: Computations

Partners: Indaver, K.U. Leuven - TME

Objective: Computation of the flow in a furnace.

Period: Jun 2003 – Nov 2003

Contact: E. Van den Bulck, M. Vanierschot

3.10.3Bilateral project with Maxon: Computations

Partners: Maxon, K.U. Leuven - TME

Objective: Computation of the flow through a channel with burners

Period: Mar 2003 – Nov 2003

Contact: E. Van den Bulck, M. Vanierschot

3.10.4Bilateral project with LABORELEC: Renting of measuring equipment

Partners: LABORELEC, K.U. Leuven - TME

Objective: Renting of exhaust measuring equipment as a back-up for monitoring of gas turbines.

Period: Jul 2002 – Jun 2003

Contact: E. Van den Bulck

3.10.5Bilateral project with ARCH Timber Protection: Feasibility study of pyrolysis as a possible disposal method for impregnated wood waste.

Partners: ARCH Timber Protection, K.U.Leuven - TME

Objective: This project aims to answer the single question whether or not chromated copper arsenate (CCA) treated wood waste can be thermally treated to facilitate the recovery of arsenic without even a minor release of arsenic as vapour. Due to the ban on the sale of arsenic-treated wood to consumers and a restriction of its use to a limited number of essential industrial applications, alternatives for CCA impregnation solutions are brought on the market. The absence of arsenic in these copper-based preservatives may enlarge the range of temperatures and residence times that may be used in the pyrolysis process. The thermal behaviour of wood waste impregnated with copper-based preservatives is studied in order to determine the working conditions of the pyrolysis process.

Period: Sep 2002 – Aug 2004

Contact: L. Helsen, E. Van den Bulck

3.11Safety engineering

3.11.1Bilateral project with DSM Fibre Intermediates: : Experimental and theoretical study of the explosion and detonation hazards during the production of caprolactam

Partners: K.U.Leuven - TME - DSM Fibre Intermediates

Objective: To assess the explosion and detonation risks involved with the production of caprolactam, several hazardous scenarios have been put forward for two process units of the plant: the Hyam Reactor and the Toluene Stripper. The first group of scenarios gives rise to an explosive atmosphere of methane, hydrogen and nitrous oxide in the Hyam Reactor. In order to evaluate the explosion risks involved, mixture compositions are calculated and explosion characteristics (limits and peak pressures) of CH₄/H₂/N₂O mixtures are measured for the actual conditions in the reactor. Other scenarios give rise to an explosive atmosphere of toluene and nitrous oxide in the exhaust pipe of the Toluene Stripper. To evaluate the explosion and detonation risks involved, explosion characteristics (limits and peak pressures) of toluene/N₂O mixtures are measured for the actual conditions in the exhaust of the stripper. The detonation behaviour of the mixtures is assessed based upon measurements of the peak pressure and the rate of pressure rise during an explosion. All experiments are carried out in a closed vessel apparatus with a design pressure of 3500 bar and a volume of 8 litre.

Period: Nov 2002 – Mar 2003

Contact: F. Verplaetsen, J. Berghmans

3.11.2Bilateral project with Physikalisch Technische Bundesanstalt: Temperature and pressure dependences of explosion characteristics

Partners: K.U.Leuven - TME - PTB Braunschweig

Objective: This scientific collaboration aims at the development of models for the influence of temperature and pressure on the flammability limits, the explosion pressure and the auto-ignition temperature of gas mixtures. Experiments at non-atmospheric conditions will be carried out in different explosion vessels in order to obtain a comprehensive set of experimental data and to validate the developed calculation models.

Period: Jan 2002 – Dec 2004

Contact: F. Verplaetsen, J. Berghmans

3.12Biomedical engineering

3.12.1ESA and Prodex - Investigations into a potential mechano-transduction and gravity transducer mechanism in osteoblasts, using optical methods

Partners: D. Jones (Philipps University, Marburg), G. Carmeliet (K.U.Leuven)

Objective: This project aims at investigating the role of the intra-cellular free calcium (IFC) in the mechanical transduction process in osteoblast cells under microgravity conditions. Changes in IFC are correlated with a quantified mechanical straining of the osteoblast cells. A straining device is developed for this purpose. The consequences of changes in the IFC upon a number of important biochemical processes are visualised by means of dyes. Also, changes in genetic expression will be visualised. During the experiments the interaction between mechanical and hormonal stimulation will be investigated as well. This research will yield additional insight in the mechanisms of load-induced bone remodelling, which has potential applications in the prevention and treatment of bone metabolic diseases such as osteoporosis.

Period: January 1996 – June 2003

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.2ESA and Prodex - Marrow Biopack – Stimuli

Partners: M. Wevers (K.U.Leuven)

Objective: The dynamics of bone remodelling under microgravity conditions is important, e.g. concerning bone loss during prolonged space flight. In literature, explanations are suggested based both on the lack of impact-loads in space, as well as on perturbations in hormonal equilibrium. But since the mechanism of bone remodeling is not yet fully understood in normal conditions, it is all the more obscure under microgravity conditions. The aim of this project is the development of a bone chamber in which a sample of trabecular bone remains vital for prolonged period. This will be realized by incorporating a perfusion system and also by enabling cyclic mechanical loading of the sample. With this system it should be possible to detect small changes in mechanical properties, biochemistry and bone morphology. Moreover the influence of mechanical and hormonal parameters on bone metabolism can be studied.

Period: September 2000 – August 2004

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.3F.W.O.-project - Mathematical modelling and simulation of mechanically induced skeletal tissue differentation

Objective: Cells in skeletal tissues are sensitive to mechanical stimuli. Interactions between the mechanical environment and the cell’s biochemistry play a role in the differentiation of pluripotent mesenchymal cells to osteoblasts, like during fracture healing and healing of skeletal implants. In order to obtain regeneration of the undifferentiated tissue to bone tissue instead of formation of fibrous scar tissue, the mechanical environment must be controlled. This research project wants to contribute to a better understanding of the influence of mechanical loading (stresses, strains, strain rate, hydraulic effects) on the tissue differentiation processes around immediately loaded skeletal implants. This will be achieved by combining mathematical modelling with animal experimental research. The mathematical model will take into account fluid-structure interaction in the differentiating tissues and the differentiation process will be simulated. A bone chamber will be used in the animal experiments in order to study the relation between well-defined mechanical stimuli and the observed differentiation processes. The numerical simulations will be validated by means of data from the animal experiments.

Period: October 2000 – September 2003

Contact: G. Van Der Perre, J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.4G.B.O.U.-project: Improved Objective Whole-Body Vibration Comfort Parameters based upon Refined Spine and Buttocks Modelling and Muscle Fatigue Detection

Partners: H. Ramon (K.U.Leuven), R. Van Audekercke (K.U.Leuven), G. Vanderstraeten (R.U.G.)

Objective: The excess of back pain in drivers is often considered to be due to exposure to whole-body vibration. The objective of this project is therefore to understand the spinal movements caused by vibrations, to identify the importance of different vibration frequencies and body postures, and to reveal the injury mechanisms that are responsible for low back pain.

An improved insight in human behaviour towards vibration exposure is achieved by building a combined full spine-buttocks model: improved knowledge is gathered on buttock vibration attenuation behaviour and on the role of the buttocks as transmission path of vibration towards the spine. Further this model is linked to muscle behaviour and to physiological changes through heat development, in order to provide objective means for comfort and health evaluation of specific vibration exposure. State of the art EMG data processing techniques, wavelet tools and classification schemes are used for this purpose.

Finally a vibration simulator (6 degrees of freedom) is used to control the parameters of interest and to eliminate all disturbing factors. Professional driving tests are performed, and files containing all vibration characteristics of these tests are simulated and used to optimise and validate the human model.

Period: September 2001 - August 2005

Contact: R. Van Audekercke

URL: http://www.vibracom.be

3.12.5EU FP5 GROWTH project - Innovative coating of temperature sensitive medical implants with biofunctional materials using Electron Beam Ablation (INCOMED G5RD-CT-2001-00533)

Partners: Co-ordinator: C. Schultheiss, Forschungszentrum Karlsruhe GmbH (DE); Contractors: K.U.Leuven-BMGO (J. Vander Sloten) & K.U. Leuven-MTM (J. Van Humbeeck); BIOMATECH SA (FR) (R. Eloy), Teer Coating Limited (GB) (D. Teer - M. Jarrat), gb Implant-Technology (DE) (A. Piotrowski)

Objective: INCOMED concerns coating of temperature sensitive subcutaneous and transcutaneous implant objects with a thin layer of hydroxylapatite (HA), bioactive glass (BAG) or mixtures of both. The aim is to obtain implantable devices with good soft tissue anchoring to inhibit infections and rejection phenomena between implant and soft tissue. This should result in at least 90 % reduction of complications or infections due to incompatibility of implant material with tissue. The coating technique is pulsed electron beam ablation (ELBA). ELBA allows coating of plastic, flexible tubes, cables, electrodes etc. with bioactive materials. The methods used at K.U. Leuven will be physical and chemical materials characterisation (by profilometry, SEM, XPS, XRF...), in vitro testing and computer modelling.

Period: October 2001 – September 2004

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.6IDO – project (interdisciplinary research programmes): “Tissue Engineering: optimalisation of osteogenesis with titanium membranes using osteogenic cell populations, mechanical stimulation and bioactive coatings.” Project Nr. 3M010195

Partners: Co-ordinator: F. Luyten, Research Division for arthritis and metabolic bone diseases, Faculty of Medicine; D. van Steenberghe, Division Parodontology; I. Naert, E. Schepers, Division Prosthetic Dentistry; J. Van Humbeeck, Department Metallurgy & Materials Engineering (MTM); G. Van der Perre, Division Biomechanics and Engineering Design (BMGO)

Objective: to develop new protocols for enhanced bone regeneration. Specifically, the relative importance of three stimulation methods will be studied: biological, mechanical and chemical stimulation (by means of cell expansion/differentiation technology, dynamic loading and bioactive coatings, respectively). Optimal cell culture and/or loading regimes to initiate the differentiation of precursor cells to in vivo bone forming cells will be identified. Ultrasonic waves (US) and Periperal Quantitative Computed Tomography (pQCT) will be developed and evaluated as techniques for in situ monitoring of bone maturation under a titanium membrane. Protocols to optimise a bioactive glass coating will be developed. The final objective is rapid, reproducible and permanent formation of bone with sufficient mechanical strength under a titanium membrane. This bone formation will be verified in animal trials.

Period: September 2001 – August 2004

Contact: G. Van Der Perre

URL: http://mech.kuleuven.ac.be/bmgo

3.12.7IWT project MATERIALISE-KUL – Biomechanisch & grafisch ondersteunde planningsomgeving voor harde-weefsel chirurgie (BIOPLAN)

Partners: Co-ordinator: W. Vancraen, Materialise N.V., Leuven, (Belgium)

Contractors: Materialise N.V. (W. Vancraen) & K.U.Leuven-BMGO (J. Vander Sloten)

Objective: BIOPLAN concerns the integration of software tools for biomechanical evaluation of skeletal surgical interventions in a pre-operative and image-based planning environment. At first dental implantology is chosen as the field of application. The aim is to biomechanically evaluate a pre-operative placement plan of dental implants in the lower or the upper jaw. Thus the user should receive some relevant information with respect to possible biomechanical / clinical problems related to the plan he made, e.g. risk of overload of an implant. Also some indications should be given to the user to improve the plan. A key issue is that the biomechanical information must be generated with minimal input from the user and as fast as possible. The task of the K.U.Leuven is to generate a biomechanical model for this purpose and to evaluate it.

Period: February 2002 – January 2005

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.8EU.-project (fifth framework): Contact-free Dynamical Optical Measuring System for Whole Body Scanning with Functional Analysis Capacity of the Spine and the Musculo-skeletal System (4D Body scan)

Partners: Diers International GmbH (H. Diers), Biomechanics and Engineering Design, K.U.Leuven (J. Vander Sloten, R. Van Audekercke, B. Haex), Custom8 NV (K. Van Brussel), Velomat GmbH (R. Wunderwald), Medical Communications GmbH (M. Schinkman)

Background: The amount of people suffering from different musculo-skeletal complaints, such as low back pain, is huge, and is by far the most important cause for work absenteeism. Orthopaedic physicians and physiotherapists are required to analyse a variety of movements to diagnose pathological or abnormal changes of the spine.

Objectives: The aim of the project is to develop a system able to reconstruct musculo-skeletal movements of the spine, which can be applied to a wide range of static and dynamic applications. White light raster line triangulation will be used as the basic technique to record a body part in 4D (3D + time), and anatomical and physiological models able to reconstruct the musculo-skeletal system of the scanned body parts are developed to indicate and quantify pathological changes or abnormalities, both at an early stage and in connection with diagnosis and therapy. The main advantages will be the equipment's ability to reconstruct kinematics and dynamics of the musculo-skeletal system, without the use of potentially harmful or expensive equipment.

Period: September 2002 - September 2004

Contact: J. Vander Sloten, B. Haex, R. Van Audekercke

URL: http://mech.kuleuven.ac.be/bmgo

3.12.9FWO project – New procedures in robot assisted surgery: definition and implementation of robot 'skills'

Partners: J. De Schutter, K.U.Leuven-PMA, H. Bruyninckx, K.U.Leuven-PMA

Objective: Within this project high level surgical tasks which can be applied to robot manipulator systems will be defined and implemented. These so-called robot 'skills' can be subdivided into a number of subtasks which has to be adapted to the robot system and coordinated in a control strategy.
One of the main issues in this project is to realize the 'intelligent' reaction of the robot on changes in the environment. These can be provided by sensor information and include for example tissue movements as well as individual organ dimensions of patients. To proof the feasibility of the chosen skills of different surgical domains (including orthopedics and cardiology) and the defined procedures prototype strategies under laboratory conditions will be developed.

Period: January 2003 – December 2006

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.10GBOU project – Guided Bone Engineering: Healing of Large Bone Defects (GBE)

Partners: Co-ordinator: J. Schrooten, K.U.Leuven-MTM; Contractors: K.U.Leuven-BMGO (J. Vander Sloten); K.U.Leuven-MTM (J. Van Humbeeck); K.U.Leuven-Laboratory of Skeletal Development and Joint Disorders (F. Luyten); U.Ghent-Polymer Materials Research Group (E. Schacht); VITO-Ceramics Processing and Powder Metallurgy (B) (J. Luyten)

Objective: GBE investigates the use of a tissue engineering oriented approach for the repair of large bone defects in load bearing parts of the skeleton. The repair mechanism used is not natural fracture healing but a controlled stimulation of bone formation, with the goal to obtain a durable repair of large bone defects. To this end new biomechanically optimized porous structures will be manufactured, coated and biologically activated by loading them with cells and biological agents. These structures will be evaluated in vitro (cell culture) and in vivo (animal models) for their suitability as a bone engineering implant. The structures will be polymers, ceramics and metals, either used as a load bearing implant, or in combination with an external fixator. The methods used at BMGO will be numerical modeling for the biomechanical optimization of the structures, and mechanical engineering design for development of part of the in vitro experimental set-up and the external fixator.

Period: January 2003 – December 2006

Contact: J. Vander Sloten

URL: http://www.tissue-engineering.be

3.12.11EU FP5 Quality of Life Project – Improving implant fixation by immediate loading (IMLOAD) QLK6-CT-2002-02442

Partners: Co-ordinator: I. Naert, K.U.Leuven-Prosthetic Dentistry with K.U.Leuven-BMGO (J. Vander Sloten), K.U.Leuven-ESAT/MICAS (B. Puers), K.U.Leuven-MTM (M. Wevers); contractors: University Medical Centre Nijmegen (J. Jansen), Royal Veterinary College (A. Goodship) with University of Bath (subcontractor to RVC) (J. Cunningham), University of Wales College of Medicine (J. Middleton), Materialise NV (B. Swaelens), Astra Tech AB (S. Hansson), MSC.Software GmbH (R. van Dijk).

Objectives: The project will investigate the mechanical aspects of osseointegration of metallic implants used for permucosal and percutaneous fixation of prostheses.

An oral rehabilitation protocol will be developed to control the mechanical conditions to optimise the speed and quality of osseointegration, thereby maximizing the success rate of implant-retained prostheses while minimizing the rehabilitation time for patients.

The oral rehabilitation protocol, combined with a “smart prosthesis”, should lead to a rehabilitation period that is significantly reduced when compared to control patients. The implant failure rate in patients using the smart prosthesis should also be significantly reduced when compared to controls.

Period: January 2003 – December 2005

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.12OT-project OT/03/31 “The role of biomechanical parameters in the success or failure of cementless orthopaedic implants”

Partners: Promotor G. Van der Perre (BMGO), co-promotors: J. Vander Sloten, J. Van Audekercke (BMGO), G. Fabry (Orthopaedics Section, Faculty of Medicine), A. Spaepen (Laboratory for Ergonomics , Faculty of Kinesiology and Rehabilitation Sciences)

Objectives: The scope of the research is focussed in two ways: (1) only cementless fixation (i.e. by osseointegration) of total hip replacements (THR) will be studied. (2) The proposed research focuses on primary fixation during the healing phase and the next few months, until a stable interface between implant and host bone has been realised. The effect of the initial healing phase on the long-term failure or success is also an essential part of the study. The scientific objective of the proposed biomechanical analysis is to establish a relationship between biomechanical parameters, more specificly the load bearing capacity of an implant and the surrounding bone as well as the load during functional activity, and the quality of the initial fixation of the implant. Additionally, the analysis of initial mechanical fixation will be validated and parameters obtained will be used in the validation of the methodology in a prospective patient study. After completion and validation in a prospective patient study, the methodology will be used as a screening mechanism for patients at risk of implant failure.

Period: October 2003-September 2006

Contact: G. Van Der Perre

URL: http://mech.kuleuven.ac.be/bmgo

3.12.13ESA and Prodex: Development of a space flight experiment for investigating the influence of high frequency low amplitude mechanical stimulation.

Partners: D. Jones (Philipps University Marburg), G. Carmeliet (K.U.Leuven), G. Richards (AO Research Institute Davos), L. Vico (Inserm St. Etienne)

Objective: This project will investigate the role of high frequency and low amplitude mechanical stimulation in an ex vivo bone/loading device under microgravity conditions. Hardware for miniaturisation of the current laboratory equipment is currently being developed. Method: Histological sections will be evaluated and compared with µCT data and FE modelling for 6 loaded (30 Hz, 0.3g) and 6 unloaded bone samples both for a ground and a space experiment. An unmanned space flight opportunity is foreseen in 2006 (Foton M3).

Period: September 2002 – end 2006

Contact: J. Vander Sloten

URL: http://mech.kuleuven.ac.be/bmgo

3.12.14Design of safer helmets for cyclists

Partners: Neurosurgery, K.U.Leuven (J. Goffin), Biomechanics and Engineering Design, K.U.Leuven (G. Van der Perre, J. Vander Sloten, B. Haex), Agricultural Engineering, K.U.Leuven (D. Berckmans)

Background: Epidemiological studies on bicycle accidents show that a substantial fraction of the cyclists that call for medical aid, are suffering from skull and brain damage; furthermore, cranio-cerebral traumas are a direct cause for the majority of the fatal accidents. However, the bicycle helmets that are commercially available could be improved considerably: they do not cover the temple of the head (which is sensitive to fractures and subsequent injuries), they do not offer protection against rotational accelerations, and their thermo-dynamical characteristics are far from perfect.

Objectives: The objective is to develop a 3D mathematical simulation model of a virtual human for the simulation of biological responses. More specifically, the aim is to develop a DBM model of a virtual human head consisting of two parts, namely a model describing the thermal responses of the head in time and space and a model describing the mechanical responses in time and space. The thermal model aims at describing the dynamic response to micro-environmental variables (e.g. air temperature and humidity), while the mechanical model aims at describing the dynamic response of skull and brain to mechanical impacts and to vibration. Next to mathematical modelling, experiments will be carried out to investigate the pathogenesis of neurotrauma in cycling accidents. The final aim is to make use of these experimental and modelling data to improve the design of bicycle helmets.

Period: September 2003 - September 2007

Contact: G. Van der Perre, J. Vander Sloten, B. Haex

URL: http://mech.kuleuven.ac.be/bmgo