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Computational fluid dynamic (CFD) numerical simulations are providing alternative to experimental methods in preliminary analysis of aerodynamic behavior for large wind turbines. Shortcomings inherent by experimental methods have popularized the three dimensional CFD methods. This paper, therefore, presents a numerical analysis for NREL 5MW wind turbine rotor using a single moving reference frame approach. ANSYS Fluent is employed to model airflow over the blade's surfaces using Reynolds average Navier-Stokes equations. A steady-state incompressible pressure based solver is applied in form of absolute velocity formulation. Four turbulence models are used: k − SST, k − RNG, k − realizable and Spalart Allmaras to determine the aerodynamic torque. Mesh independence study and validation is also performed. In addition, the predicted flap-wise bending load and comparison of pressure distribution for the four turbulence models are evaluated at different sections of the blade. Due to absence of experimental data for employed blade model, the obtained aerodynamic torque was compared with other reliable numerical simulation results.

Effectiveness and efficiency of hydro-cyclone separators are highly dependent on their geometrical parameters and flow characteristics. Performance of the hydro-cyclone can, therefore, be improved by modifying the geometrical parameters or flow characteristics. The mining and chemical industries are faced with problems of separating ore-rich stones from the nonorerich stones. Due to this problem a certain amount of precious metals is lost to the dumping sites. Plant managers try to solve these problems by stockpiling what could be useless stones, so that they can be reprocessed in the future. Reprocessing is not a sustainable approach, because the reprocessed material would give lower yield as compared to the production costs. Particulate separation in a hydro-cyclone has been investigated in this paper, by using computational fluid dynamics. The paper investigated the influence of various flow and geometric parameters on particulate separation. Optimal parameters for efficient separation have been determined for the density of fluid, diameter of the spigot, and diameter of the vortex finder. The principal contribution of this paper is that key parameters for design optimization of the hydro-cyclone have been investigated.

The purpose of present study is to approve use of ANSYS software as a tool for wind turbine simulations. Based on workbench platform designmodeler, mechanical mesh and fluent components, the study attempts to reproduce experimental measurements performed on standstill outboard MEXICO blade section in the low speed low turbulence (LTT), a facility at Delft University of Technology. The outboard MEXICO blade section geometry same as the one used in experiments is adopted for numerical simulations. Three set of angle of attack are taken as variable with inlet velocity hold at 35 m/s and fluid flow viscosity at 1.462kgms −2 in every simulation. Steady state pressure based solver is utilized to solve continuity and momentum Navier-Stoke equations with k − ω SST turbulent model taken as closure. Pressure and velocity are decoupled via SIMPLE algorithm and discretization scheme specified to second order upwind for momentum, turbulent kinetic energy and dissipation rate, while pressure interpolation scheme settled to second order. Computed pressure coefficient around selected airfoil sections is compared to experiment measurements which include; RISOE_121 at 60%R and NACA64418 at 92%R. Comparison shows good agreement between the CFD simulation and experiment results, but slight variation is observed at around RISOE_121 airfoil.

In this paper, a design optimisation technique for mixing in a gas