Optimization methodology of turbomachines for hybrid SOFC–GT applications

The objective of this work is to suggest a method for optimizing the compressor and turbine components in hybrid SOFC–GT (Solid Oxide Fuel Cell – Gas Turbine) applications. The hybrid system evaluations are made on the basis of a typical SOFC generator scheme without any modifications. The method consists of two steps. A parametric study is conducted in order to assess the operating range of the hybrid SOFC–GT system and select the desired operating line for achieving the optimum system efficiency at various operating points. Based on that information, optimum compressor and turbine geometries are estimated using in-house turbomachinery design codes and an optimization procedure. The new components ensure the best performance not only in the design point but also during part-load operation. The results of the present analysis are useful for designing hybrid SOFC–GT systems based on a fixed SOFC generator design.