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Showing 1 to 20 of 36 for “"K Epsilon"”.
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Application of a modified k-[epsilon] turbulence model to gas turbine combustor geometries
The k-epsilon turbulence model yields inconsistent and diffusive results for swirling and recirculating flows, which are characteristic of combustor geometries. Y. S. Chen and S. W. Kim propose a modification to the k-epsilon turbulence model which has shown improved predictions for several complex …
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Numerical Simulation of Injection and Mixing in Supersonic Flow
… of two renormalized group theory (RNG) based k-epsilon turbulence models with a more conventional k-epsilon model. The chosen designs were an unswept ramp injector with four injection ports and a novel nine-hole injector array. The objectives of the investigation were to provide reliable …
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Applications of Lie Groups in Turbulence Modeling
… is applied to the general two-dimensional k-epsilon turbulence model. Symmetry algebras for the k-epsilon turbulence model have been calculated by Khor'kova. and Verbovetsky. This systematic approach is applied to the specific flow problem of turbulent submerged free plane jets. Similarity …
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Gas-liquid simulation of an airlift bubble column reactor
… simulation is described by using the K-Epsilon model, RNG K-Epsilon model and K-Omega model. This process occurs under atmospheric pressure. The volume fraction of model is described the behavior of bubble which is represented by the parameters of gas hold up, contact surface area and …
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Entwicklung eines Reynolds-Spannungs-Modells zur Modellierung turbulenter Sprayflammen
… durch Vergleiche mit Simulationen, die das k-epsilon-Modell verwenden, sowie Experimenten an einem reagierenden und nicht reagierenden Methanolspray verifiziert. Numerische Simulationen mit dem neuen RSM für Sprayflammen liefern im Vergleich zum k-epsilon-Modell zusätzlich die Varianzen und …
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3D Numerical Modeling of the Turbulent Flow in Hydraulic Structures
… meshes. A FEM flow solver was used with the k-epsilon model as the turbulence closure. The rigid-lid assumption was employed to simplify the modeling of the water surface. The MPI parallization of the code and the utilization of high-performance supercomputers made the resulting intensive …
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Beyond Arrows: Energy Performance of a New, Naturally Ventilated Double-Skin Facade Configuration for a High-Rise Office Building in Chicago
… floor plan layout were evaluated using the k-epsilon model. • Models to simulate the specific DSF typology and couple the envelope-level results to a building simulation program. • A framework for comparing and evaluating the conventional facade solution with a new configuration of …
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Near-wall modeling of bubbly flows
… for liquid and gas phases, as well as the k-epsilon turbulence model with modifications to account for the presence of bubbles. The resulting partial differential equations require well-posed boundary conditions, with special treatment at the walls, where there exist strong gradients of all …
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Numerical study on internal flow structures of subaqueous density underflows and stratified open-channel flows
… in the stability functions, such as QE k-epsilon and Mellor-Yamada models, yield better performance than the standard k-epsilon and constant eddy viscosity models in capturing stratification effects. Two key limitations are identified for all the two-equation RANS models presented in this …
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Turbulence models for the numerical prediction of transitional flows with RANSE
… Spalart-Allmaras, two-equation models such as k-epsilon, k-omegaSST, three-equation model kkl-omega as RANS solvers, LES solvers and DES Solvers. The validation of OpenFoam based solver and the different turbulence models is made on the prediction of the friction and pressure drag components as …
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Turbulence in Multiphase Models for Aeration Bubble Plumes
… includes a treatment of turbulence via a k - epsilon model and a Large-Eddy Simulation (LES) approach. It is based on a double averaging procedure that accounts for: (a) the presence of a two-phase flow, and (b) its turbulent nature. The model also allows for the global simulation of phenomena …
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Prediction of turbulent mixing at the interface of density stratified, shear flows using CFD
… scalar transport multiphase model and the k-epsilon turbulence model were used. In the simulations involving miscible fluids an interfacial thickness relationship given by delta/H∼(Ri*)--2.1 and an entrainment relationship given by E∼(Ri*)--1.1 were predicted. These relationships …
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Approximate k-means clustering through random projections
… k-rank approximation problems to within (1 + [epsilon]) error. Importantly, this class of problems includes k-means clustering. By reducing data points to just O(k) dimensions, our methods generically accelerate any exact, approximate, or heuristic algorithm for these ubiquitous problems. For …
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Axial Compressor Design with Counter-Rotation and Variable RPM for Stall Mitigation
… and exit static pressure condition with k-epsilon as the turbulence model. Compressor exit conditions are then changed to stall the compressor. After the compressor stalls the RPM of the counter-rotating stage is varied until the compressor recovers from the stall. This novel idea unlike …
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Turbulent mixing of unpremixed reactants in stirred tanks.
… the flow within the tank. This program uses a k-epsilon closure of the turbulent momentum equations. The program was modified to allow the inclusion of a segregation balance equation. Using this segregation balance technique, the turbulent species balance equations were solved. The results of …
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The influence of steps topography on the behavior of density currents – a numerical study
… a lock-exchange setup were conducted using k-epsilon, two-dimensional and three-dimensional Large Eddy Simulation (LES) models. The results of the present study clearly indicate that compared with a constant slope bed, vertical steps, or “stair-case” shaped bed topographies significantly …
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Sampling-based algorithms for dimension reduction
… We prove that using a sample of roughly O(k/[epsilon]) rows of A one can compute, with high probability, a (1 + [epsilon])-approximation to the nearest rank-k matrix. This gives an algorithm for low-rank approximation with an improved error guarantee (compared to the additive [epsilon]... …
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Numerical Analysis of an Axial Flow Horizontal Axis Marine Hydrokinetic Turbine
… the sliding mesh technique. The realizable k-epsilon model is employed to solve the closure problem. The methodology is validated against experimental data measured in open channel tests conducted at the St. Anthony Falls Laboratory of the University of Minnesota, in collaboration with Sandia …
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Computational fluid dynamics modelling of displacement natural ventilation.
… The two benchmarks are defined using the RNG k-epsilon turbulence model. A pressure boundary is applied onto the ventilation openings directly and a porous medium boundary is used to assist the development of the thermal plume. This method has proved to be robust and the close agreement between …
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Numerical Simulations and Studies on Round Jet Impingement, Twin Jet Impingement and Helicopter Rotor Blades Ground Effect
… Reynolds-Averaged Navier-Stokes equations with K-epsilon (k-ε) turbulence model are solved using the commercial CFD solver ANSYS FLUENT. For jet exit near the flat ground surface and water surface, some interesting differences in flow phenomenon are obtained due to that ground is rigid and water …
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