An experimental investigation of stator induced unsteadiness on centrifugal impeller outflow

Journal Article · Mon Jan 01 04:00:00 EST 1996 · Journal of Turbomachinery

DOI:https://doi.org/10.1115/1.2836604· OSTI ID:194217

Ubaldi, M; Zunino, P; Barigozzi, G; Cattanei, A ^[1]

---

1. Univ. di Genova (Italy). Ist. di Macchine e Sistemi Energetici

Detailed flow measurements were taken in a centrifugal turbomachine model to investigate the aerodynamic influence of the vaned diffuser on the impeller flow. The model consists of an unshrouded centrifugal impeller with backswept blades and a rotatable vaned diffuser, which enables a continuous variation of the vaned diffuser location with respect to the measuring points. Phase-locked ensemble-averaged velocity components have been measured with hot-wire probes at the impeller outlet for 30 different relative positions of the probe with respect to the diffuser vanes. The data also include the distribution of the ensemble-averaged static pressure at the impeller front end, taken by means of miniature fast response pressure transducers flush-mounted at the impeller stationary casing. By circumferentially averaging the results obtained for the different circumferential probe locations, the periodically perturbed impeller flow has been split into a relative steady flow and a stator-generated unsteadiness. The results for the different probe positions have also been correlated in time to obtain instantaneous flow field images in the relative frame, which provide information on the various aspects of the diffuser vane upstream influence on the relative flow leaving the impeller.

• Sponsoring Organization: USDOE
• OSTI ID: 194217
• Report Number(s): CONF-940626--
• Journal Information: Journal of Turbomachinery, Journal Name: Journal of Turbomachinery Journal Issue: 1 Vol. 118; ISSN JOTUEI; ISSN 0889-504X
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
GAS FLOW
MATHEMATICAL MODELS
STANDING WAVES
TURBOMACHINERY
UNSTEADY FLOW