http://hdl.handle.net/10900/83729 2026-10-03T02:58:02Z http://hdl.handle.net/10900/83816 Numerical Simulation of Heat Transfer in Turbulent Pipe Flow with Structured Wall Surfaces Renze, Peter Innovative heat transfer technology is the key to the optimization of many processes in the power or process industry. Operational costs and usage of valuable resources can be reduced, if the heat transfer efficiency is increased and pressure loss is reduced. Therefore, the current work is focused on heat transfer enhancement at tubes with micro-structured walls with turbulent flow. In this kind of geometry modern optical measurement technology cannot be applied and the analysis of the turbulent transport is only possible with numerical flow simulations. A large-eddy turbulence model is applied to account for turbulence closures. First, the simulation setup is validated with data from the literature and then several micro-structured geometries are investigated. The simulations are computationally costly and depend on high performance computing (HPC). The open-source software library OpenFOAM® is applied to perform massively parallel simulations. 2018-08-14T00:00:00Z http://hdl.handle.net/10900/83815 Virtualized Research Environments on the bwForCluster NEMO Janczyk, Michael; Wiebelt, Bernd; von Suchodoletz, Dirk The bwForCluster NEMO offers high performance computing resources to three quite different scientific communities (Elementary Particle Physics, Neuroscience and Microsystems Engineering) encompassing more than 200 individual researchers. To provide a broad range of software packages and deal with the individual requirements, the NEMO operators seek novel approaches to cluster operation [1]. Virtualized Research Environments (VREs) can help to both separate different software environments as well as the responsibilities for maintaining the software stack. Research groups become more independent from the base software environment defined by the cluster operators. Operating VREs brings advantages like scientific reproducibility, but may introduce caveats like lost cycles or the need for layered job scheduling. VREs might open advanced possibilities as e.g. job migration or checkpointing. 2018-08-14T00:00:00Z http://hdl.handle.net/10900/83812 HPC-based uncertainty quantification for fluidstructure coupling in medical engineering Kratzke, Jonas; Heuveline, Vincent In recent decades biomedical studies with living probands (in vivo) and artificial experiments (in vitro) have been complemented more and more by computation and simulation (in silico). In silico techniques for medical engineering can give for example enhanced information for the diagnosis and risk stratification of cardiovascular disease, one of the most occurring causes of death in the developed countries. Other use cases for in silico methods are given by virtual prototyping and the simulation of possible surgery outcomes. High reliability is a requirement for cardiovascular diagnosis and risk stratification methods especially with surgical decision-making. Given uncertainties in the input data of a simulation, this implies a necessity to quantify the uncertainties in simulation results. Uncertainties can be propagated within a numerical simulation by methods of Uncertainty Quantification (UQ). 2018-08-14T00:00:00Z http://hdl.handle.net/10900/83808 Empirical Charge Scheme for Transition Metals and Lanthanoids: Development and Applications Martin, Bodo R.; Comba, Peter Parameters for the fluctuating charge model are derived for In(III), La(III), Lu(III) and Bi(III), based on x-ray structural data and DFT single point calculations. A number of density partitioning schemes is tested. 2018-08-14T00:00:00Z