RT - Journal Article T1 - Numerical investigation of turbulence characteristics of flow in fixed and oscillating transonic fan cascade JF - mdrsjrns YR - 2015 JO - mdrsjrns VO - 14 IS - 16 UR - http://mme.modares.ac.ir/article-15-12382-en.html SP - 231 EP - 242 K1 - "Turbomachines Turbulence Flow" K1 - " Oscillating Cascade" K1 - "Transonic Flow" K1 - "Transonic Fan" AB - Investigations of the phenomena associate with the Fluid-Structure interactionin transonic turbomachines due to the presence of unstable flow behaviors have double significance. Severe restrictions of the experimental methods, has developed researchers approach in this field to Numerical methods. Nevertheless, using simple two-dimensional model to investigate the phenomenon of quality is inevitable because of high computational cost of numerical methods in aerodynamic and aeroelastic simulation of full model of turbomachines. In this paper transonic flow in fixed fan cascade and fan cascade with central blade vibration in Forced harmonic pattern is simulated and variations of turbulence characteristic patterns are studied. In order to prevent divergence of the solution and achieve more accurate results, the step by step algorithm is developed. On the other hand, spring methodology with linear torsional springs is used for movement of dynamic grid around the oscillating blade. Mesh quality is assessed by examining maximum Mach number and y+ variation. Compare the results with the available experimental data indicated a significant difference in the position of the vortices are detached and re-attached. This difference proves need to use a turbulence model is more accurate in terms of the wide separation. In this paper, effect of blade geometry, flow separation and central blade oscillation on flow pattern and turbulence characteristics of transonic flow have been investigated. Obtained results explain the effect of mentioned parameters on the turbulence kinetic energy and dissipation frequency. LA eng UL http://mme.modares.ac.ir/article-15-12382-en.html M3 ER -