Computational fluid dynamics analysis of 1 MW steam turbine inlet geometries

This paper analyses the influence of three different ring-type inlet duct geometries on the performance of a small 1 MW backpressure steam turbine. It examines the efficiency and pressure drop of seven turbine variants, including four spiral inlet geometries and three stages with a mass flow rate around 30 t/h. A one-pipe and two-pipe inlets are analysed from aerodynamical point of view, taking into account stator and rotor blades in three stages without the outlet. An outlet is added to the best variant. Also analysed is the occurrence of vortices in the inlets of the studied variants 1–7 as well as the efficiency, drop pressure, turbine power and mass flow. Finally, the best inlet for a 1 MW steam turbine is suggested

Computational fluid dynamics analysis of several designs of a Curtis wheel

In small steam turbines, sometimes the efficiency is not as important as the cost of manufacturing the turbine. The Curtis wheel is a solution allowing to develop a low output turbine of compact size and with a low number of stages. This paper presents three fully dimensional computational fluid dynamics cases of a Curtis stage with full and partial admission. A 1 MW steam turbine with a Curtis stage have been designed. The fully admitted stage reaches a power of over 3 MW. In order to limit its output power to about 1 MW, the partial admission was applied. Five variants of the Curtis stage partial admission were analyzed. Theoretical relations were used to predict the partial admission losses which were compared with a three-dimensional simulations. An analysis of the flow and forces acting on rotor blades was also performed

Influence of inlet geometry on the efficiency of 1 MW steam turbine

The process of the design of the 1 MW steam turbine includes designing the stator and rotor blades, the steam turbine inlet and exit, the casing and the rotor. A turbine that operates at rotation speeds other than 3000 rpm requires a gearbox and generator with complex electronic software. This article analyses the efficiency of eight turbine variants, including seven inlet geometries and three stages of stator as well as an eight variant with one of the inlets, all three stages and an outlet. This article analyses the efficiency of 8 turbine variants, including four spiral inlet geometries and tree stages in a 1 MW steam turbine. In the article, inlets and 1st stator blades of various geometries were analysed to obtain maximal turbine efficiency. Changing the inlet spiral from one pipe to two pipes increased the turbine efficiency. The geometry of the blades and turbine inlets and outlet was carried out using Design Modeller. The blade mesh was prepared in TurboGrid and inlet in ANSYS Meshing