The Mixing of Water and Diesel Fuel at Close Proximity of Combustion Cans in GE 9HA’s Emulsification System

摘要

GE’s 9HAs is a heavy duty gas turbine (GT) offering higher efficiency and power output second to none. It has an advanced liquid fuel system with an emulsification technology. The distribution of water and fuel to each combustion can is achieved by water and fuel manifolds. The mixing of water and liquid fuel occurs at the combustion can level, in proximity to the combustion nozzles as required for better combustion and system anti-coking. The mixing of water and fuel is controlled by multiple mixing valves located at each combustor. The aim of the emulsification system is to provide substantially uniform fuel and water flow to all of the combustion cans. The variation requirements are both in the total flow and the water fuel ratio for all the nozzles. A multi-specie (oil and water) flow network model was created to simulate the water and liquid fuel flow rates to fuel nozzles for system development. The major focus is the evaluation of the impact of manufacturing tolerances within the fuel nozzles and the mixing valve flow coefficients (Cv), in additional to the elevation difference of these cans. An engine test at full speed full load in Greenville, South Carolina demonstrated the system had achieved the desired total flow uniformity as well as water fuel ratio uniformity.