Application of alcohol vapour as atomizing fluid in a micro gas turbine burner

Liquid fuels have to be atomized before combustion. In micro gas turbines twin-fluid atomizers are widely used for this purpose. In this type of atomizers generally high velocity air flow disintegrates the liquid fuel stream into droplets, but superheated vapour can also be applied as atomizing fluid. In our experiments a burner of a Capstone C30 micro gas turbine was used, which was built into a test rig developed by us. During measurements diesel oil was used as liquid fuel. Atomizing fluids were air and aqueous ethyl alcohol vapour at different pressures. In every combustion experiment, emissions of carbon monoxide, unburned hydrocarbons and nitrogen oxides were measured. The results showed that application of alcohol vapour as atomizing fluid instead of air improves the quality of combustion. Increasing the atomizing pressure up to a defined optimum value also reduces emissions significantly.