After having specified a Design case type, run a design point calculation by clicking the run button (green arrow) or press F9 in the project window. With the design point calculation, the gas turbine design point performance is fixed to represent a particular gas turbine configuration. The components are "sized" to the design point using data from the Design tab sheets (data from other tab sheets that do normally not change in off-design operation other than by user specification are also used for the design calculation such as compressor bleed and turbine cooling data). The turbine design point calculation for example determines turbine flow rate capacity that represents geometry in terms of effective flow area of the stator nozzle. For the design point calculation, the component maps are not used but scale factors are calculated instead for scaling of the maps during subsequent off-design calculations (see the following sections). A design point calculation is always necessary before off-design, steady state or transient calculations, since the design point is used as the reference point for off-design operating points. Note that a design point calculation resets off-design input parameters in the General and certain other tab sheets back to their design values, if Auto Reset Input to Design is checked in Options|General.
Design point calculation
