costs associated with them but is also costly when done frequently. That is why substantial efforts have been invested in minimizing the expected total cost due to failures and preventive maintenance of industrial equipment (Dekker 1996, Tan and Kramer 1997, Bäckert and Rippin 1985, Dekker and Scarf 1998). In industry, most preventive-maintenance approaches include the use of fixed schedules, o...

The flow in the gap between an inner rotating cylinder concentric with an outer stationary cylinder with an imposed pressure-driven axial flow was studied experimentally using particle image velocimetry ~PIV! in a meridional plane of the annulus. The radius ratio was h50.83 and the aspect ratio was G547. Velocity vector fields for nonwavy toroidal and helical vortices show the axial flow windin...

Renewable energy sources include solar, wind, hydro, geothermal and biomass. Furthermore, ocean is being rapidly harnessed worldwide. In this study, to establish a suitable design method for various bidirectional ducted tidal turbines, instead of using blade element momentum theory CFD, which have been used previously, the turbomachinery was designing turbines. A turbine optimises equipment red...

The performance prediction of axial flow compressors at different speeds and under various pressure ratio conditions are still being developed because of costly empirical experiments. One-dimensional modeling is a simple, fast and accurate method for performance prediction in any type of compressor with different geometries. In this approach, inlet flow conditions and compressor geometry are kn...

In this paper it is attempted to investigate the behavior of an inviscid flow in the meridional plane of an axial flow compressor. For this purpose the 3-D unsteady Euler equations in cylindrical coordinate are averaged in tangential direction. Therefore, the equations are reduced to a 2-D system. By averaging the tangential component of momentum equation, a blade force will result. Axial and r...

Large-eddy simulations of pairs of artificially generated longitudinal vortices embedded in a two-dimensional turbulent boundary layer are performed to study the dynamics of the vortical structures and to provide the unsteady inflow data for use in a future turbomachinery simulation. An immersed boundarymethod is employed to represent the wall-mounted half-delta wings that generate the counter-...

In this paper it is attempted to investigate the behavior of an inviscid flow in the meridional plane of an axial flow compressor. For this purpose the 3-D unsteady Euler equations in cylindrical coordinate are averaged in tangential direction. Therefore, the equations are reduced to a 2-D system. By averaging the tangential component of momentum equation, a blade force will result. Axial and r...