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Gas-solid flows are present in many industries such as Oil & Gas and Chemical Processes, and can be measured experimentally or by numerical simulations. This work presents the results of both. The experiments were conducted in a test facility where vertical and horizontal sections of a pipe were selected as probing stations with radial profiles for axial solid velocities, obtained using Particle Image Velocimetry (PIV) technique. The test operating conditions behaved as a dilute flow and the solid particles had similar diameter compared to those applied in FCC units. The numerical...
The effect of the atmospherical dispersion of pollutants (chemical products…) in the close range of the dispersion site is a growing concern both from utilities and from regulation bodies. As a matter of fact, the traditional methods (based on statistical approach) are not valid at a distance below 100m. Some simplified tools exist on the market but they are not well suited to complex sites where buildings can strongly interact with the wind. Over the past few years, AREVA has developed and validated for its own need a CFD method based on STAR-CCM+ to describe in detail the atmospherical...
MYRRHA is an experimental nuclear reactor whose design is under development at the Belgium Nuclear Agency SCK•CEN. In the framework of the FP7 SEARCH and MAXSIMA European projects, CRS4 is giving contributions to the design, making the CFD modelling with STAR-CCM+ of parts of the nuclear systems and of related experimental setups. We present here the two most recent ones. The first application regards the construction of a CFD model of the entire primary coolant loop of MYRRHA which combines a thermal flow with free surfaces and driven by hydraulic pumps. The heat provided by the reacting...
This presentation highlights features of STAR-CCM+ which make it market leader for simulation of flow and motion of floating bodies within marine and offshore industry. Examples of applications by customers are used to highlight the software capabilities and to prove the benefits of simulation. This is followed by presenting the new features that are currently under development and targeting specifically marine and offshore applications, e.g. extensions of motion modeling to allow various combinations of prescribed and free motion (like PMM-tests), extension of cavitation model, internal wave...
Up-to-date marine propellers are designed to accompany a certain extent of cavitation for optimum propulsive efficiency, but excessive extent and certain types of cavitation have the risk of high hull pressure pulse, blade surface erosion and thrust break down. Propeller cavitation becomes unsteady and complex due to the interaction of the propeller flow and the non-uniform wake field behind the hull. The Kappel propeller is an innovative tip-modified propeller, which shows higher propulsive efficiency and lower hull pressure pulse than conventional propellers. Unsteady cavitation simulations...
Numerical simulations of the flow along azimuthing thruster units are becoming more mature these days. A number of steps have been made during the last decade in RANS simulations. Initially the full scale unit performance, being thrust output and power requirement, has been determined for the steady-state condition. Next the time dependent forces, which are a result of the blades passing the strut, have been quantified. These analyses have been made initially for a single unit with uniform inflow and afterwards for two units, where the jet of the upstream thruster is directed towards the...
The wing-sail is an interesting idea for sailboats, and the last America’s Cup showed that its use is possible and very effective. At the University of Pisa it was decided to use this type of sail on the small boat realised for the inter-university race “ 1001 vele ”. A first wing sail has been used in 2013 with satisfactory results, but it was evident that high improvement in the performances can be obtained. The performances of this system are impressive, but the flow is complex and the number of geometrical parameters are very high. In order to tackle this problem resort was made to a...
This paper describes author’s experience with numerical modeling of ship-propeller interaction using the CFD tools of STAR-CCM+. The two numerical approaches considered in the paper are presented by an iterative viscous/potential coupled method , where propeller effect in the main RANS solution is represented by an actuator disk model, which is coupled with an external panel method code for propeller analysis, and an unsteady RANS method, where interaction between the hull and propeller is resolved by a time-accurate Sliding Mesh procedure. Detailed comparisons with experimental data done for...
Ocean going ships undergo significant loading at sea and are designed to survive severe sea states in an intact condition. However, little consideration is given to the structural integrity of vessels which are damaged. This can be attributed to the limited knowledge of ship responses in their damaged state. An assessment on the viability of the commercial CFD package STAR-CCM+ as a tool for assessing damaged ships has been undertaken by Lougheed (2012) and Goatly (2013). A model was set up emulating experimental damaged hull sections oscillating in a tank with RANS and LES turbulence models...
ABB Marine is using STAR-CCM+ for the Azipod-units CFD simulation. In this study, open water performance of the pod unit and simulated hydrodynamic loads at varied steering angles at full scale are presented. Open water performance of the pulling-type propeller and pod unit are determined by three approaches: RANS CFD simulations by quasi-steady moving reference frame and unsteady sliding mesh approaches and by model scale experiments for validation. The sliding mesh technique is applied for capturing hydrodynamic loads on the pod and propeller surfaces at varied steering angles. These loads...

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