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This paper presents a throughflow analysis tool developed in the context of the average-passage flow model elaborated by Adamczyk. The Adamczyk's flow model describes the 3-D timeaveraged flow field within a blade row passage. The set of equations that governs this flow field is obtained by performing a Reynolds averaging, a time averaging and a passage-to-passage averaging on the Navier-Stokes equations. The throughflow level of approximation is obtained by performing an additional circumferential averaging on the 3-D average-passage flow.The resulting set of equations is similar to the 2-D axisymmetric Navier-Stokes equations but additional terms resulting from the averages show up : blade forces, blade blockage factor, Reynolds stresses, deterministic stresses, passage-to-passage stresses and circumferential stresses. This set of equations represents the ultimate throughflow model provided that all stresses and blade forces can be modeled. The relative importance of these additional terms is studied in the present contribution.The stresses and the blade forces are determined from 3-D steady and unsteady databases (a low speed compressor stage and a transonic turbine stage) and incorporated in a throughflow model based on the axisymmetric Navier-Stokes equations. A good agreement between the throughflow solution and the averaged 3-D results is obtained. These results are also compared to those obtained with a more "classical" throughflow approach based on a Navier-Stokes formulation for the endwall losses, correlations for profile losses and a simple radial mixing model assuming turbulent diffusion. INTRODUCTIONThe throughflow level of approximation still remains an important tool for designing turbomachines [10] even though 3-D calculations are used more and more early in the design process. Throughflow codes are mainly used at the preliminary design stage for specifying the target aerodynamic performances to be achieved by the blading. They can be used either in the design mode, where the angular momentum and/or the total conditions are prescribed and the flow angles are sought, either in the analysis mode, where a known machine geometry is analyzed for its performance. The throughflow models are also used to exploit experimental results or to couple single blade row calculations in order to compute the flow field inside a multistage machine [4].Unfortunately, these models heavily rely on empirical inputs, such as profile losses correlations or end-wall loss models. They can accurately predict the flow field inside a turbomachine provided that the design parameters are not too far from those of the reference machines that were used to calibrate the throughflow model. This approach has shown to be efficient but lacks of generality.The most widespread throughflow method is certainly the streamline curvature method (SLC). In 1980, Spuur has proposed another approach based on the Euler equations. This approach has only started to retain attention in the 1990. Recent works using this approach can be foun...