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A computational study of the process of sedimentation of spherical particles in suspensions with high particle concentrations has been performed with the two-fluid Eulerian approach. The solid stress induction in the dispersed phase was modelled through modification of the suspension viscosity. Convectional flow patterns were found and studied during the simulations. The presence of these patterns, which are also observed experimentally, makes the sedimentation process dependant on the rheological behaviour of the suspension. The results of the simulation were validated with experimental...
Traditionally, the analysis of two-phase boiling flows has relied on experimentally-derived correlations as the bases of the analysis. While this approach provides accurate predictions of channel-averaged temperatures and void fractions and even peak assembly temperatures within an assembly, it lacks the resolution needed to predict the detailed intra-channel distributions of temperature, void fraction and steaming rates that are needed to address the fuel reliability concerns which result from longer refueling cycles and higher burnup fuels, particularly for the prediction of potential fuel...
Numerical analyses are presented to explain the effect of drop size and contact angle on local pressures inside small channels. These pressures and channel characteristics are of interest when water condenses in the gas channels of Proton Exchange Membrane Fuel Cells and hence the study uses Reynolds numbers consistent with as typical utilization of reacting gases in 200 cm2 flow fields (i.e., 200 < Re < 1500 and stoichiometries of 1.2–2.0 at 1.0 A/cm2). The analyses were performed using three-dimensional computational fluid dynamic techniques and the results show that pressure drops...
An aerosol rapid compression machine is developed to investigate energetic-nanoparticleenhanced combustion of liquid fuels using ethanol and aluminum nanoparticles as a model system. An ultrasonic nozzle is used to nebulize neat ethanol and mixtures containing nanoparticles for ignition delay tests in the rapid compression machine. It is determined that 2%-weight nano-aluminum can lead to a dramatic reduction in the ignition delay (90%). The aerosol is introduced to the rapid compression machine through a poppet valve that is optimized by CFD simulations to maximize turbulent mixing and...
The transport industries face a continuing demand from customers and regulators to improve the acoustic performance of their products: reduce noise heard by passengers and passersby; avoid exciting structural modes. In both the aerospace and automotive areas, flow-induced noise makes a significant contribution, leading to the desire to understand and optimize it through the use of simulation. Historically, the need for time-consuming, computationally expensive transient simulations has limited the application of CFD in the field of acoustics. In this paper are described efficient simulation...
The transport industries face a continuing demand from customers and regulators to improve the acoustic performance of their products: reduce noise heard by passengers and passersby; avoid exciting structural modes. In both the aerospace and automotive areas, flow-induced noise makes a significant contribution, leading to the desire to understand and optimize it through the use of simulation. Historically, the need for time-consuming, computationally expensive transient simulations has limited the application of CFD in the field of acoustics. In this paper are described efficient simulation...
The CFD simulation of diesel combustion needs as accurate initial values as possible to be reliable. In this paper the effect of spatial distribution of state and turbulence values at intake valve closure to those distributions prior to SOI is studied.Totally five cases of intake and compression stroke simulations are run. The only change between cases is the intake boundary condition of turbulence. In the last case the average values of p, T, k, ε and swirl number at intake valve closure are used as initial values to compression simulation.The turbulence in the engine cylinder is mainly...
Detailed computational fluid dynamics models of mineral insulated metal sheath thermocouples are discussed, and thermocouple readings in clean flames are verified against experimental thermocouple data for a Hencken burner flame available in the literature. Computational results present thermocouple temperature readings as a function of thermocouple insertion depth in threedimensional directions. Computational temperature correlations are plotted against nondimensional insertion depth and insertion height above the burner. Overall predictions showed excellent agreement with experimental data...

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