The main subject of the present publication is the comparison of results achieved with a 3D-partially parabolic calculation procedure and experimental data for the three dimensional flow in stationary and rotating blade rows of axial flow compressors.
To set up the numerical solution procedure, the Navier-Stokes Equations are written in finite difference form by applying the control-volume approach. The turbulent flow effects are taken into account by using the standard k—ε model for the calculation of the turbulent viscosity. For precisely introducing the boundary conditions for arbitrary geometries, the differential equations are transformed to a body-fitted coordinate system by a very simple method. To construct the physical mesh, the nonorthogonal curvilinear coordinates are taken as solutions of a suitable elliptic boundary value problem.
The abilities of the developed computer program are shown by comparing experimental and numerical results for three applications. The first, most simple case deals with the flow development in an isolated, stationary blade row of cylindrical blades and uniform boundary conditions upstream of the blade row. A more complex flow is regarded by calculating the flow field through highly turned, custom tailored airfoils working in a multistage environment. The flow conditions upstream of the flow domain under consideration show a well developed end wall boundary layer at the hub, leading to a strongly skewed inflow due to the superimposed tangential velocity component of the rotor upstream. The third application regards the flow development in a rotating axial compressor blade row in which the complexity of the flow field increases by flow effects that are due to centrifugal and Coriolis forces.
The comparisons between experimental and numerical results show good agreements for all applications.