CFD SIMULATION OF WATER INJECTION IN GT INLET DUCT USING SPRAY EXPERIMENTALLY TUNED DATA: NOZZLE SPRAY SIMULATION MODEL AND RESULTS FOR AN APPLICATION TO A HEAVY-DUTY GAS TURBINE

摘要

This study describes an application of Computational Flow Dynamics (CFD) to the two-phase flow problem of water injection into a compressor inlet duct for fogging systems. The paper addresses issues related to the CFD setup and the developed spray simulation model. Water injection is simulated by fitting experimental data on sprays obtained from industrial nozzles. In particular, the initial droplets size distribution is defined in accordance with results of laboratory tests on impaction-pin type nozzles. By using a commercial CFD software, 3D numerical simulations have been carried out on a typical gas turbine inlet duct. The effects of the duct geometry, filter and silencer on the duct internal air flow-field were analyzed. Finally, the effect of water injection carried out by means of an array of nozzles in the inlet duct is investigated. The paper presents the CFD two-phase results obtained for the application case under study; the analysis of the compressor bellmouth conditions due to the evaporation phenomenon is included in the paper.