Computational Fluid Flow analysis in Cryogenic Turbo expander

Abstract

Cryogenic turbo expander is one of the components used in cryogenic plant to achieve low temperature refrigeration. Basic components in cryogenic Turbo expander are Turbine wheel, brake Compressor, shaft, nozzle, Thrust bearing, Journal Bearing etc. In expansion Turbine Temperature of gases decreases due to expansion and produces coldest level of Refrigeration. This project is all about Computational Fluid flow analysis of high speed rotating turbine. This involves with the three dimensional analysis of flow through a radial expansion turbine, using nitrogen as flowing fluid. Cfd packages, Bladegen, Turbogrid and CFX are used to carry out the analysis. Bladegen is used to create the model of turbine using available data of hub, shroud and blade profile. Turbogrid is used to mesh the model. CFX-Pre is used to define the physical parameters of the flow through the Turbo expander. CFX-Post is used for examining and analyzing results. Using these results variation of different thermodynamic properties like Temperature, Pressure, density, velocity etc inside the turbine can be seen. Several graphs are plotted showing the variation of velocity, pressure, temperature, entropy and Mach number along streamline and span wise to analyze the flow through cryogenic turbine