Sebastian Kornet

The effort of the steam turbine caused by a flood wave load

Development of the Thermal-FSI (Fluid Solid Interaction) let to accurate the process of cooling the steam turbine set. It provide to shorter times of maintenance and repairs of the turbine sets. The cooling of the steam turbine which temperature exceeds 500°C can take time of one week. Insulation and housing is taken off when temperature reaches 100°C. In analysis was applied thermal-FSI which takes into account temperature changes between solid material and fluid. In the paper authors propose this way to estimate effort of the turbine structure caused by an intrusion of water into the flow channels.

Numerical analysis of the oscillation frequency of the shock wave and the evaporation level on the Mach disc in the IMP PAN nozzle

In the present paper, we have focused on the phenomena occurring in the supersonic part of the de Laval nozzle, characterised by oscillation of the shock wave in steam flow. The effect of shock oscillation was observed by using the Topler optical system in the IMP PAN experiment carried out on a symmetrical planar de Laval nozzle. Having observed the shock fluctuation in wet steam flow, according to Puzyrewskis observations, we analysed the oscillation frequency in the IMP PAN nozzle depending on the pressure conditions. Additionally, we analysed the evaporation level of condensate droplets during passage through the Mach disc depending on the inlet conditions. The model of a single continuum wet steam model with a special microstructure growing up during phase transitions was validated on an experiment carried out by Dykas et al. in 2013 on the half arc nozzle. The present work includes simulations results of oscillation frequency of the shock wave and the evaporation level of the liquid phase on the Mach disc.

An asymmetrical λ-foot of condensing steam flow in the IMP PAN nozzle

In the present paper we have focused on the precise prediction of the spontaneous condensation phenomena in wet steam flow. Novelty of our approach lies on modelling both the moment of initiation of a phase transition, as well as the moment of its reverse progress - called here re-vaporization of the condensate phase. The practical issue is to elaborate of a model of spontaneous condensation/vaporization of water steam flow under low-pressure conditions by using methodology of non-equilibrium thermodynamics [2]. The basic tests including comparison with an experimental data have been performed using the IMP PAN nozzle with the de Laval geometry [1]. Having observed the finishing of a foggy flow within the shock wave, according to Puzyrewski’s postulate [1], we would like to analyse the topography of the shock wave pattern in the IMP PAN symmetric nozzle. This phenomenon, independently from a type of compressible fluid, has been observed to be the result of interaction between a normal shock wave and the boundary layer – it has been known as a lambda-foot structure [3]. The asymmetry of the shock structure is measured by optical system and visible since the foggy flow can be easily observed. Our paper is a trial towards to an explanation of this problem.