Search Results - "Krepper, E."

Experimental investigation of two-phase pipe flow with ultrafast X-ray tomography and comparison with state-of-the-art CFD simulations by Banowski, Manuel, Hampel, Uwe, Krepper, E., Beyer, M., Lucas, Dirk

“…In this paper, we report on experimental investigations of air/water two-phase flow in a vertical pipe, which is a benchmark experiment for the development and…”
Get full text

CFD-simulation of boiling in a heated pipe including flow pattern transitions using the GENTOP concept by Höhne, T., Krepper, E., Montoya, G., Lucas, D.

“…•Boiling flow inside a wall heated vertical pipe is simulated by a multi-field CFD approach.•The paper presents the extension of the GENTOP model for phase…”
Get full text

Validation of CFD models for mono- and polydisperse air–water two-phase flows in pipes by Frank, Th, Zwart, P.J., Krepper, E., Prasser, H.-M., Lucas, D.

“…Many flow regimes in nuclear reactor safety (NRS) research and nuclear reactor engineering are characterized by water–steam two-phase flows and require for…”
Get full text

A strategy for the qualification of multi-fluid approaches for nuclear reactor safety by Lucas, D., Rzehak, R., Krepper, E., Ziegenhein, Th, Liao, Y., Kriebitzsch, S., Apanasevich, P.

“…CFD-simulations for two-phase flows applying the multi-fluid approach are not yet qualified to provide reliable predictions for unknown flows. Among others,…”
Get full text

Simulation of gas–liquid flow in a helical static mixer by Zidouni, F., Krepper, E., Rzehak, R., Rabha, S., Schubert, M., Hampel, U.

“…CFD simulations using the Euler–Euler approach are performed to model the gas–liquid bubbly flow in a helical static mixer. The model validation work was based…”
Get full text

Use of models for lift, wall and turbulent dispersion forces acting on bubbles for poly-disperse flows by Lucas, D., Krepper, E., Prasser, H.-M.

“…Closure laws are needed for the qualification of CFD codes for two-phase flows. In case of bubbly and slug flow, forces acting on the bubbles usually model the…”
Get full text

Development of co-current air–water flow in a vertical pipe by Lucas, D., Krepper, E., Prasser, H.-M.

“…Measurements of the cross-sectional distribution of the gas fraction and bubble size distributions were conducted in a vertical pipe with an inner diameter of…”
Get full text

General guideline for closure model development for gas-liquid flows in the multi-fluid framework by Lucas, D., Krepper, E., Liao, Y., Rzehak, R., Ziegenhein, T.

“…The two- or multi-fluid approach is frequently used for Nuclear Reactor Safety (NRS)-related simulations of gas-liquid flows. To enable reliable predictions…”
Get full text

Two-scale CFD analysis of a spent fuel pool involving partially uncovered fuel storage racks by Oertel, Ronald, Hanisch, T., Krepper, E., Lucas, D., Rüdiger, F., Fröhlich, J.

“…•Simulation of a spent fuel pool with partially exposed fuel assemblies by means of CFD.•Investigation on the pool and reactor building as well as on the fuel…”
Get full text

Gas–liquid flows in medium and large vertical pipes by Duan, X.Y., Cheung, S.C.P., Yeoh, G.H., Tu, J.Y., Krepper, E., Lucas, D.

“…Gas–liquid bubbly flows with wide range of bubble sizes are commonly encountered in many industrial gas–liquid flow systems. To assess the performances of two…”
Get full text

CFD Analysis of a Void Distribution Benchmark of the NUPEC PSBT Tests : Model Calibration and Influence of Turbulence Modelling by Krepper, Eckhard, Rzehak, Roland

“…The paper presents CFD calculations of the void distribution tests of the PSBT benchmark using ANSYS CFX-12.1. First, relevant aspects of the implemented wall…”
Get full text

Classification of bubbles in vertical gas–liquid flow: Part 1 – An analysis of experimental data by Qi, F.S., Yeoh, G.H., Cheung, S.C.P., Tu, J.Y., Krepper, E., Lucas, D.

“…► Analyze two-phase flows in a large diameter pipe under various flow regimes. ► Classifying bubbles of different shapes into two spherical or cap bubble…”
Get full text

Application of CFD Codes in Nuclear Reactor Safety Analysis by Hoehne, Thomas, Rohde, U., Krepper, E.

“…Computational Fluid Dynamics (CFD) is increasingly being used in nuclear reactor safety (NRS) analyses as a tool that enables safety relevant phenomena…”
Get full text

Implementation of a strainer model for calculating the pressure drop across beds of compressible, fibrous materials by Grahn, A., Krepper, E., Alt, S., Kästner, W.

“…Mineral wool insulation debris, which is generated during a loss-of-coolant-accident (LOCA), has the potential to undermine the long-term recirculation…”
Get full text

Experimental study on bubble motion in a rectangular bubble column using high-speed video observations by Zaruba, A., Krepper, E., Prasser, H.-M., Reddy Vanga, B.N.

“…A two-phase flow in a rectangular bubble column of 100×20 mm cross-section and 1.5 mm height was studied using a high-speed video system. Series of images were…”
Get full text

Measurement of bubble velocity profiles and turbulent diffusion coefficients of the gaseous phase in rectangular bubble column using image processing by Zaruba, A., Krepper, E., Prasser, H.-M., Schleicher, E.

“…The flow in a rectangular bubble column with a cross-section of 100 × 20 mm and a height of 1500 mm was studied using a high-speed video-system. Series of the…”
Get full text

Investigations on the Stability of the Flow Characteristics in a Bubble Column by Lucas, D., Krepper, E., Prasser, H.-M., Manera, A.

“…The role of the lift force in the stability of the homogeneous flow regime in a bubble column is investigated. Instabilities caused by the lift force may be…”
Get full text

Evaluation of computational fluid dynamic methods for reactor safety analysis (ECORA) by Scheuerer, M., Heitsch, M., Menter, F., Egorov, Y., Toth, I., Bestion, D., Pigny, S., Paillere, H., Martin, A., Boucker, M., Krepper, E., Willemsen, S., Muhlbauer, P., Andreani, M., Smith, B., Karlsson, R., Henriksson, M., Hemstrom, B., Karppinen, I., Kimber, G.

“…The objective of the ECORA project is the evaluation of computational fluid dynamics (CFD) software for reactor safety applications, resulting in best practice…”
Get full text

Review of Available Data for Validation of Nuresim Two-Phase CFD Software Applied to CHF Investigations by Krepper, E., Lucas, D., Moretti, Fabio, Galassi, Maria Cristina, Macek, J., Vyskocil, L., Končar, Boštjan, Hazi, G., Bestion, Dominique, Ničeno, B., Andreani, M., Smith, B. L., Anglart, H., Caraghiaur, D., Péturaud, P.

“…The NURESIM Project of the 6th European Framework Program initiated the development of a new-generation common European Standard Software Platform for nuclear…”
Get full text

Investigation of natural convection in large pools by Krepper, E., Hicken, E.-F., Jaegers, H.

“…Natural convection is a basic principle for a lot of industrial processes. As an example for the investigation of natural convection phenomena, the paper…”
Get full text