The purpose of this work has been to develop a quasi-three-dimensional blade design and analysis system incorporating fully linked throughflow, blade-to-blade and blade section stacking programs. In Part I of the paper, the throughflow analysis is developed. This is based on a rigorous passage averaging technique to derive throughflow equations valid inside a blade row. The advantages of this approach are that the meridional streamsurface does not have to be of a prescribed shape, and by introducing density weighted averages the continuity equation is of an exact form. Included in the equations are the effects of blade blockage, blade forces, blade-to-blade variations and loss. The solution of the equations is developed for the well-known streamline curvature method, and the contributions from these extra effects on the radial equilibrium equation are discussed. Part II of the paper incorporates the analysis into a quasi-three-dimensional computing system and demonstrates its operational feasibility.

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Performance calculations for a NASA controlled-diffusion compressor blade have been carried out with a coupled inviscid-boundary layer code and a time-marching Navier-Stokes solver. Comparisons with experimental test data highlight and explain the strengths and limitations of both these computational methods. The boundary layer code gives good results at and near design conditions. Loss predictions however deteriorated at off-design incidences. This is mainly due to a problem with leading edge laminar separation bubble modelling; coupled with an inability of the calculations to grow the turbulent boundary layer at a correct rate in a strong adverse pressure gradient. Navier-Stokes loss predictions on the other hand are creditable throughout the whole incidence range, except at extreme positive incidence where turbulence modeling problems similar to those of the coupled boundary layer code are observed. The main drawback for the Navier-Stokes code is the slow rate of convergence for these low Mach number cases. Plans are currently under review to address this problem. Both codes give excellent predictions of the blade surface pressure distributions for all the cases considered.

The purpose of this paper is to show, for both rotating and non-rotating blade rows, the importance of including circumferential non-uniform flow effects in a quasi-three-dimensional blade design system. The paper follows on from previous publications on the system in which the mathematical analysis and computerised system are detailed. Results are presented for a different stack of the nozzle guide vane presented previously and for a turbine rotor. In the former case it is again found that the blade force represents a major contribution to the radial pressure gradient, while for the rotor the radial pressure gradient it is dominated by centrifugal effects. In both examples the effects of circumferential non-uniformities are detailed and discussed.

The purpose of this work has been to develop a quasi-three-dimensional blade design and analysis system. In Part II of the paper the computerized blade design system is presented and an example given to illustrate its use. The system comprises a streamline curvature throughflow program incorporating the analysis of Part I of this paper, a blade section stacking program, and one of a number of blade-to-blade calculation programs. The information flow between each part of the system is described and the importance of each stage in the calculation indicated. Information is transferred between programs via a data base which enables other design programs, e.g., heat transfer programs, to access the results. This modular approach enables individual design program advances to be made relatively easily. The system is flexible enough to incorporate a number of blade-to-blade programs, the one used depending on the specific application. An example of the flow through a turbine nozzle guide vane is presented. Experimental data are compared with the results from the quasi-three-dimensional system, a fully three-dimensional program and an unlinked two-dimensional system. The results from the quasi-three-dimensional system are very encouraging.