TY - JOUR
T1 - Steady and unsteady condensate formation in turbomachinery - Blade to blade flow and rotor/stator intéraction
AU - Schnerr, G. H.
AU - Heiler, M.
AU - Winkler, G.
PY - 1998
Y1 - 1998
N2 - Worldwide, most of the electrical power plants have been in service for more than 25 years and continuous development of CFD codes has made possible the detailed calculation of complex single phase flows in turbine stages. However, commercially available codes do neither contain adequate representation of the steam phase transition mechanism, nor the corresponding condensation loss (Smith, 1991). Therefore, we concentrate on the dynamics of instabilities typical for condensing steam or steam/carrier gas mixtures in the dominating transonic flow regime. Neglecting viscosity effects of the fluid numerical simulations based on the Euler equations confirmed the existence of self-excited flow oscillations in realistic blade configurations of low pressure steam turbines. In linear cascades higher order bifurcations with sudden frequency increase or decrease can develop. As a first approach the forced excitation mechanism of the rotor/stator interaction is modelled by unsteady temperature wake effects which alter significantly the two-phase flow characteristics.
AB - Worldwide, most of the electrical power plants have been in service for more than 25 years and continuous development of CFD codes has made possible the detailed calculation of complex single phase flows in turbine stages. However, commercially available codes do neither contain adequate representation of the steam phase transition mechanism, nor the corresponding condensation loss (Smith, 1991). Therefore, we concentrate on the dynamics of instabilities typical for condensing steam or steam/carrier gas mixtures in the dominating transonic flow regime. Neglecting viscosity effects of the fluid numerical simulations based on the Euler equations confirmed the existence of self-excited flow oscillations in realistic blade configurations of low pressure steam turbines. In linear cascades higher order bifurcations with sudden frequency increase or decrease can develop. As a first approach the forced excitation mechanism of the rotor/stator interaction is modelled by unsteady temperature wake effects which alter significantly the two-phase flow characteristics.
UR - http://www.scopus.com/inward/record.url?scp=0346928414&partnerID=8YFLogxK
U2 - 10.1615/MultScienTechn.v10.i4.30
DO - 10.1615/MultScienTechn.v10.i4.30
M3 - Article
AN - SCOPUS:0346928414
SN - 0276-1459
VL - 10
SP - 349
EP - 368
JO - Multiphase Science and Technology
JF - Multiphase Science and Technology
IS - 4
ER -