One problem with many introductory level turbomachinery courses is a lack of easy to use design and visualization tools. Oftentimes students will become too focused on the underlying math and never develop a good understanding of the physical systems they are working with. To combat this problem, a series of GUI based design and visualization codes have been created. The codes are intended primarily for educational purposes, but in many cases they are robust enough for actual design use. All of the new codes have been designed to complement and to a small extent connect to the existing T-Axi suite of codes. This paper will focus on two new freely available codes: T-Axi Blade and T-Axi Disk. T-Axi Blade was created to help visualize the key design features of a single rotor, with special emphasis on vector triangles, and the ability to design compressor, turbine, axial and centrifugal rotors with a universal approach. T-Axi Blade can also output files for use with T-Axi Disk, a code to aid in the design of a lightweight disk to support the blade row. This code allows the user to design a disk interactively with instantaneous feedback in the form of weights, stresses, and a series of 2D and 3D visualizations. Taken together these codes offer a simple introduction to multidisciplinary engineering. In this paper the structure of these codes and the numerical models are discussed. Ideas are presented of how these codes can be used as a classroom tool and as an actual design tool. An example analysis of the third stage GE EEE HPC axial rotor is presented to demonstrate the features of these codes.

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Numerical prediction of the Stage 67 transonic fan stage employing wall jet tip injection flow control and study of the physical mechanisms leading to stall suppression and stability enhancement afforded by endwall recirculation/injection is the focus of this paper. Reynolds averaged Navier–Stokes (RANS) computations were used to perform detailed analysis of the Stage 67 configuration experimentally tested at NASA's Glenn Research Center in 2004. Time varying predictions of the stage plus recirculation and injection flowpath were executed utilizing the nonlinear harmonic (NLH) approach. Significantly higher grid resolution per passage was achieved than what has been generally employed in prior reported numerical studies of spike stall phenomena in transonic compressors. This paper focuses on characterizing the physics of spike stall embryonic stage phenomena and the influence of tip injection, resulting in experimentally and numerically demonstrated stall suppression.

Numerical prediction of the Stage 67 transonic fan stage employing wall jet tip injection flow control and study of the physical mechanisms leading to stall suppression and stability enhancement afforded by endwall recirculation/injection is the focus of this paper. Reynolds averaged Navier-Stokes computations were used to perform detailed analysis of the Stage 67 configuration experimentally tested at NASA’s Glenn Research Center in 2004. Time varying predictions of the stage plus recirculation and injection flowpath were executed utilizing the Nonlinear Harmonic approach. Significantly higher grid resolution per passage was achieved than what has been generally employed in prior reported numerical studies of spike stall phenomena in transonic compressors. This paper focuses on characterizing the physics of spike stall embryonic stage phenomena and the influence of tip injection, resulting in experimentally and numerically demonstrated stall suppression.

The paper describes the application of an optimization method to the redesign of a turbocharger compressor wheel. The starting design presents quite high performance. Previous attempts to improve this design have shown it difficult to increase aerodynamic performance without compromising mechanical stress levels. The optimization methodology relies on the combination of a genetic algorithm, a neural network, a database, and user generated objective functions. The originality of the paper is that the optimization is not only coupled to a CFD solver, but also to a CSM solver, so that mechanical stresses can be included in the optimization objectives. A parametric model of the solid sector of the blade, back plate and bore zone is built and included in the optimization. The challenging turbocharger test case has allowed gaining experience with design objectives of different nature. The results show that the optimization has been able to improve the aero performance, while also decreasing the peak mechanical stress levels significantly.