Gas turbine engine ducts may have struts in the gas flow path, as well as vanes for guiding a gas flow through the duct. An integrated strut and turbine vane nozzle (ISV) forms a portion of a conventional turbine engine gas path. The ISV usually includes an outer and an inner ring connected together with struts which are airfoil-shaped in order to protect support structures and/or service lines in the inter turbine duct (ITD) portion, and airfoils/vanes in the turbine vane nozzle portion. The integration is achieved by combining the airfoil shaped strut with the airfoil shape of a corresponding one of the vanes. The ISV can be made from one integral piece or from an assembly of multiple pieces. However, it is more difficult to adjust the flow through the vane nozzle airfoil if the ISV is a single integral piece. A multiple-piece approach with segments of turbine vane nozzles allows the possibility of mixing different classes of segments in the ISV to achieve proper engine flow. However, a significant challenge in a multiple-piece arrangement of an ISV, is to minimize interface mismatch between the parts in order to reduce engine performance losses. Conventionally, complex manufacturing techniques are used to minimize this mismatch between the parts of the integrated strut and vane. In addition, mechanical joints such as bolts are conventionally used, but are problematic because of potential bolt seizing in the hot environment of the ISV.
USPTO Backgrounds
USPTO Backgrounds