TRACE Overview
TRACE (Turbomachinery Research Aerodynamics Computational Environment) is a parallel 3D multi block Reynolds-Averaged Navier Stokes flow solver for both structured and unstructured meshes specifically designed to investigate turbomachinery flows.The hybrid structured / unstructured approach simplifies the simulation of auxiliary geometries such as cavities, casing treatments, bleeds and cooling holes.Simulations can be both steady state and time-accurate. For steady state simulations the moving and stationary parts of the domain are coupled by a mixing-plane approach whereas a fully conservative zonal approach is applied in the time-accurate case. Using the phase-lag method, real blade count ratios can be simulated while resolving only one passage per blade row. Inflow and outflow boundary conditions are formulated in a non-reflecting way.Turbulence is modelled by a k-w two equation model by Wilcox with turbomachinery specific extensions. This can be coupled to one of two available transition models. Further physical models are implemented for real gasses and multi phase flows.For optimization applications adjointTRACE can be used to calculate sensitivities based on the solution of the adjoined Navier Stokes equations. Aeroelastic computations can be performed using unsteady or time-linearized methods (linearTRACE).
Process
Structured meshes for turbomachine components are generated by the in-house tool G3DMESH, while commercial tools are employed for unstructured meshes. The simulation parameters, i. e. boundary conditions, connectivities, initial conditions, numerical techniques and physical models are set up with the graphical user interface GMC. After the computation of the flow solution the post processing tool POST is used to analyse the flow field e. g. with respect to turbomachine performance data.
Applications
TRACE has been successfully applied in aerodynamical, aeroacoustical and aeroelastical investigations of radial and axial turbomachinery in single- and multi-stage configurations of more than thirty blade rows.Investigated devices included wind tunnel cascades and research turbomachines as well as aircraft engine components, parts of heavy-duty gas turbines or steam turbines under various operating conditions from design point to off-design conditions.