Diffuser having distribution element for providing part-flow

A diffuser for extracting cooling air for turbine stages of a gas turbine, comprising:

• an inner wall forming a radially inner side of the diffuser;
• an outer wall forming a radially outer side of the diffuser that provides a flow passage having an inlet and an outlet where the inner and outer walls increasingly diverge along the direction of fluid flow;
• an annular passage bypassing extracted cooling air around a combustion chamber and to the turbine stages, wherein the annular passage is located radially inward of the inner wall;
• an annular distribution element arranged coaxially along a longitudinal axis and between the inner and outer walls of the diffuser having a centrally located opening that creates a cooling air part-stream of the compressor discharge fluid flow, where the distribution element opening is arranged on a leading edge of the distribution element and forms an annular opening in a central region between the outer wall and the inner wall;
• and
• a plurality of hollow lower and upper supporting elements arranged between the inner and outer walls, respectively, of the diffuser and the annular distribution element wherein at least one of the hollow lower supporting elements is in fluid communication with the annular passage.