Jochen Fröhlich

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An efficient approach for the simulation of finite-size particles with interface resolution was presented by Uhlmann (J. The present paper proposes several enhancements of this method which considerably improve the results and extend the range of applicability. An important step is a simple low-cost iterative procedure for the Euler-Lagrange coupling(More)
therefore the damping layer has to be large enough to prevent reentrant waves at the physical boundary. Hence In this paper we develop a method for the simulation of wave propagation on artificially bounded domains. The acoustic wave the approach is not only costly in terms of memory require-equation is solved at all points away from the boundaries by a(More)
The two-sample Wilcoxon rank sum test is the most popular non-parametric test for the comparison of two samples when the underlying distributions are not normal. Although the underlying distributions need not be known in detail to calculate the null distribution of the test statistic, parametric assumptions are often made to determine the power of the test(More)
The paper presents Large Eddy Simulations of plane channel flow at a friction Reynolds number of 180 and 395 with a block-structured Finite Volume method. Local grid refinement near the solid wall is employed in order to reduce the computational cost of such simulations or other simulations of wall-bounded flows. Different subgrid-scale models are employed(More)
High-order methods gain more and more attention in computational fluid dynamics. However, the potential advantage of these methods depends critically on the availability of efficient elliptic solvers. With spectral-element methods, static condensation is a common approach to reduce the number of degree of freedoms and to improve the condition of the(More)
The paper discusses the approximation of scattered data on the sphere which is one of the major tasks in geomathematics. Starting from the discretization of singular integrals on the sphere the authors devise a simple approximation method that employs locally supported spherical polynomials and does not require equidistributed grids. It is the basis for a(More)
The paper reports on DNS and LES of plane channel flow at Reτ = 180 and compares these to a DNS with a higher order convection scheme. For LES different subgrid-scale models like the Smagorinsky, the Dynamic Smagorinsky and the Dynamic Mixed Model were used with the grid being locally refined in the near-wall region. The mixing of a passive scalar has been(More)
We present Multilevel Finite Element computations for twodimensional reaction-diffusion systems modelling laminar flames. These systems are prototypes for extreme stiffness in time and space. The first of these two rather general features is accounted for by an improved control mechanism for the time step. The second one is reflected through very thin(More)