A5103172517- Brake Systems and Friction Analysis
- Adhesion, Friction, and Surface Interactions
- Tribology and Lubrication Engineering
- Tribology and Wear Analysis
- Gear and Bearing Dynamics Analysis
- Lubricants and Their Additives
- Traffic control and management
- Drilling and Well Engineering
- Tunneling and Rock Mechanics
- Vehicle Dynamics and Control Systems
- Advanced Mathematical Modeling in Engineering
- Electrical Contact Performance and Analysis
- Hydraulic Fracturing and Reservoir Analysis
- Mechanical stress and fatigue analysis
- Mathematical functions and polynomials
- Vehicle emissions and performance
- Probabilistic and Robust Engineering Design
- Vacuum and Plasma Arcs
- Cellular Automata and Applications
- Chaos control and synchronization
- Structural Health Monitoring Techniques
- Electric and Hybrid Vehicle Technologies
- Differential Equations and Boundary Problems
- Engineering and Materials Science Studies
- Advanced machining processes and optimization
Technische Universität Braunschweig
2014-2023
Fischer (Germany)
2011-2012
Grönemeyer Institute for MicroTherapy
2006-2011
Brunswick (United States)
2006
Müller BBM (Germany)
2005
In spite of remarkable efforts the perfect brake pad in terms friction performance, wear, noise, and costs has not been found to date. This is mostly because development still based on extensive ‘trial-and-error’ method, as a reliable reproduction or even prediction those issues possible. A theory regarding interaction wear interface shows that tribological behaviour system determined by growth destruction characteristic hard structures (‘patches’) mesoscopic length scale. respective...
Abstract The push in the drilling industry for longer wells, and faster more difficult trajectories leads to increasing challenges with dynamics of systems particular expensive high end offshore wells. Dynamic effects are severe occur frequently load damage tools so that mitigation by dedicated or procedures is necessary. Generally, downhole can be categorized their direction action. Vibration excited axial direction, along tool axis, mainly originates from bit rock interaction, e.g. bounce...
Polycrystalline diamond compact (PDC) bits with multiple fixed cutters drill through deep formations and are used in oil gas, geothermal, mining industry. The bit-rock interaction excites string vibrations, which need to be mitigated improve drilling performance. A velocity-weakening characteristic of the bit torque can cause severe self-excited high-frequency torsional oscillations (HFTO) bottom hole assembly (BHA). dependency on velocity attributed rate-sensitive rock cutting forces at...
Abstract Reaming while drilling (RWD) in general means to simultaneously drill a pilot hole and open it up the target diameter at same time. This could be done using an eccentric reaming device or expandable concentric underreamer; both are called reamer following. In RWD assemblies weight applied BHA is distributed between bit reamer. To ensure optimized performance drilling, it’s necessary know distribution of as well torque BHA. For any calculation string dynamics tool durability loads...
The boundary layer dynamics of brake systems is characterized by the growth and destruction hard friction intensive patterns on pad.These mesoscopic "patches" essentially determine brake's global friction-and wear behaviour.That paper shows, how, based this theory, phenomena can be simulated with an innovative dynamic law within different timescales.Subsequently a Cellular Automaton model extended definition additional inner variables describing three-dimensional surface topography pads.This...
The dynamics of friction in brake systems is correlated with the wearprocess contact area pad and disc.The time-dependence characteristic patterns wear on was used to introduce a new theory systems.With set differential equations, describing coefficient, explanations for time-variant behaviour fading effects have been found.To get an explicit insight into dynamic changing surface topography boundary layer detail we furthermore developed tool, which based discretization Cellular Automaton.In...
Starved lubrication is an important strategy for minimizing the amount of lubricant needed, and also inevitably occurs during idling fail-safe lubrication. In this regime, however, flow related friction coefficients are yet to be fully understood. This research aims make fundamental contributions understanding contact mechanics partially lubricated contacts. Recent experiments with a pin-on-disk tribometer examined microscopic behavior filled gaps. Using new experimental setup on macroscale,...
Abstract High vibrational loads occur due to self-excited high-frequency torsional oscillations (HFTO) that are excited by the bit-rock interaction while drilling in hard and dense formations. These critical vibration with an associated acceleration above 100 g can result premature failure of downhole components, leading increase non-productive time reduced reliability. Beside formation, parameters influence occurrence HFTO. This paper presents a novel method determine stable unstable...
<div class="section abstract"><div class="htmlview paragraph">Friction in tribological systems can lead to significant energy consumption and wear. While there are several dissipation mechanisms the frictional boundary layer, role of chemical processes is not fully understood. The aim this study investigate influence reactions on behavior sliding friction pairs. In order carry out initial analyses, minimal mixtures with a few simple components epoxy resin as binder developed,...
Abstract Mechanical loads in hole-opening BHAs result tool failures and generate maintenance costs non-productive time. This paper presents a method to increase the reliability of by optimally matching bit reamer. The weight torque distribution between reamer is predicted using stationary load model. New quality curves facilitate evaluation bit-reamer combinations user-friendly way. model are validated on unique set field data, enabling determination model's accuracy. based mechanical...