Search results for "TWO PHASE"
showing 4 items of 4 documents
Large eddy simulation of inertial particles dispersion in a turbulent gas-particle channel flow bounded by rough walls
2020
The purpose of this paper is to understand the capability and consistency of large eddy simulation (LES) in Eulerian–Lagrangian studies aimed at predicting inertial particle dispersion in turbulent wall-bounded flows, in the absence of ad hoc closure models in the Lagrangian equations of particle motion. The degree of improvement granted by LES models is object of debate, in terms of both accurate prediction of particle accumulation and local particle segregation; therefore, we assessed the accuracy in the prediction of the particle velocity statistics by comparison against direct numerical simulation (DNS) of a finer computational mesh, under both one-way and two-way coupling regimes. We p…
Analyses of single- and two-phase flow pressure drops in helical pipes using a modified RELAP5 code
2012
Abstract Thermal fluid dynamics analyses on single- and two-phase flows in helical pipes of steam generators to be used in Generation III and IV nuclear reactors have been performed. The study concerned with experimental activities as well code simulations carried out in the framework of a collaboration between the Department of Energetics of the Polytechnic of Torino and the Department of Energy of the University of Palermo. The goal was the validation of models implemented in Relap5/Mod3.2β thermal–hydraulic advanced code to simulate the hydrodynamic behaviour of helical pipe components in spite of the one-dimensional nature of the code. It is shown that much of the experimental data obta…
CFD predictions of turbulent two-phase flow in helical coils
2012
Turbulent two-phase flow in a helical pipe was simulated by means of CFD using the ANSYS-CFX code, based on a finite-volume multi-fluid approach. The focus was on flow patterns and frictional pressure drops; inter-phase heat and mass transfer and heat exchange with the pipe walls were not included and physical properties were assumed constant for each phase. The computational domain included a single, vertical axis, coil turn; the flow was assumed to be fully developed. Geometry and physical conditions were representative of the IRIS nuclear reactor steam generators (saturated water at 58 bar, pressure gradient of 0.1 bar/m). Void fraction and computational options (homogeneous vs. inhomo…
JSSPrediction: a Framework to Predict Protein Secondary Structures Using Integration
2006
Identifying protein secondary structures is a difficult task. Recently, a lot of software tools for protein secondary structure prediction have been produced and made available on-line, mostly with good performances. However, prediction tools work correctly for families of proteins, such that users have to know which predictor to use for a given unknown protein. We propose a framework to improve secondary structure prediction by integrating results obtained from a set of available predictors. Our contribution consists in the definition of a two phase approach: (i) select a set of predictors which have good performances with the unknown protein family, and (ii) integrate the prediction resul…