Gasabfuhrsystem für eine Gasturbine.

摘要

An exhaust system for a gas turbine has a main axial duct which feeds a heat exchanger to make use of the residual heat in the exhaust gases. The heat exchanger may in some circumstances be overloaded so a branch duct is taken from the main duct - conventionally by means of a T-junction with a flap valve closing off either the main (axial) outlet or the branch outlet. The branch duct is then taken to an exhaust stack. Turbulence at the T-junction causes poor flow upstream of the junction and corresponding poor turbine performance. The invention provides a junction in which the main axial duct (1) passes smoothly through a bypass chamber (15) which surrounds the axial duct (1). Slots (17) in the axial duct within the chamber (15) permit passage of the exhaust gases to the bypass duct (19). Rotating blade valves (13 and 23) in the two duct outlets control the relative flow of exhaust to heat exchanger and exhaust stack.