Some Aspects of Gas Turbine Fuel Preparation and Turbomachinery Response to LCV Fuels

Abstract: This thesis gives some background information on environmental issues as the scientific community at large currently sees it. It tries to relate the plethora of current combustion technologies which may be used in gas turbines to those issues. Some basic principles on combustion design are given. Different candidate fuels for gas turbine combustion are discussed. Combustion of bio-fuels is treated and provides background material for Papers 1, 4, 5, 6 and 7. Pre- and post-treatment technologies are covered briefly. Bluff body stabilized combustion is discussed in relation to Paper 3. In the case of liquid fuel combustion, the liquid must first be atomized before it can be burnt. A chapter on atomization discusses the various mechanisms involved in the break-up process of a liquid column being injected into gas. Papers 2, 8 and 9 deal with sprays. Laser based diagnostics tools are used extensively to analyze fluid flow. In Papers 2, 8 and 9 PIV and PDA have been used. An overview of these techniques is provided. Process simulation tools are used to model and analyze plants and machinery. A flow network is setup between components which act on a fluid to produce a desired outcome. The system may be a complete plant or e.g. a gas turbine. Papers 4, 5, 6 and 7 use this tool to analyze component behavior in one- and two-shaft industrial gas turbines and a combined cycle plant. All are fired with high, medium and low calorific fuels.