Abstract

Despite their low efficiency, gas turbine engines are still used for power generation, aircraft engines, and rockets. It is therefore necessary to find ways of improving the efficiency of these cycles and the consistency of the compressor flow. This research aims to reduce compressor instability, increase the operating limit and improve gas turbine performance. One of these methods is to spray water into the air at the compressor inlet. The effect of inlet water sprayers on the stable flow operating range and gas turbine performance has been investigated. A numerical analysis model without water spray is described. Then the effect of water spray is added to this model and the surge onset with and without water spray and the wet pressure processes are predicted based on the average line calculations. These analyses were necessary for the gas turbine compressor to understand the effect of water spray on the stable flow region and its effect on the efficiency of the entire gas turbine. Amounts of water ranging from 1% to 20% of the air mass were injected into the compressor through a nozzle, a valve, and an injection pump. At different operating conditions, the surge was found and considered as the compressor limit of the flow stability of the gas turbine. A simple model was used to determine the aerodynamic instability caused by stalled axial compressors. The result shows an improvement in the operating range and performance of the gas turbine.

Key words: water spraying, axial flow compressor, gas turbine, rotating stall, surge initiation