| 摘要 |
A combustor in a gas turbine engine has a wall which forms a gap with an outer nozzle guide vane platform. A closure mechanism is operable to open or close the gap. Opening of the gap, for example during cruise conditions, reduces the mass flow rate of air through an open end of the combustor, so enriching the air fuel ratio and improving flame stability and combustion efficiency. Under high power conditions, the gap is closed, causing an increase in air flow rate through the open end to achieve a lean burn air fuel ratio when the fuel flow rate is increased. |
