| Autor: |
Sangan, Carl M., Pountney, Oliver J., Zhou, Kunyuan, Wilson, Mike, Owen, J. Michael, Lock, Gary D. |
| Předmět: |
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| Zdroj: |
Journal of Turbomachinery; Mar2013, Vol. 135 Issue 2, p1-10, 10p |
| Abstrakt: |
This paper describes a new research facility which experimentally models hot gas inges-tion into the wheel-space of an axial turbine stage. Measurements of the CO2 gas concen-tration in the rim-seal region and inside the cavity are used to assess the performance of two generic (though engine-representative) rim-seal geometries in terms of the variation of concentration effectiveness with sealing flow rate. The variation of pressure in the tur-bine annulus, which governs this externally-induced (EI) ingestion, was obtained from steady pressure measurements downstream of the vanes and near the rim seal upstream of the rotating blades. Although the ingestion through the rim seal is a consequence of an unsteady, three-dimensional flow field and the cause-effect relationship between the pres-sure and the sealing effectiveness is complex, the experimental data is shown to be suc-cessfully calculated by simple effectiveness equations developed from a previously published orifice model. The data illustrate that, for similar turbine-stage velocity trian-gles, the effectiveness can be correlated using a nondimensional sealing parameter, f0. In principle, and within the limits of dimensional similitude, these correlations should apply to a geometrically-similar engine at the same operating conditions. Part II of this paper describes an experimental investigation of rotationally-induced (RI) ingress, where there is no mainstream flow and consequently no circumferential variation of external pressure. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
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