1. GE Power, Brown Boveri Strasse 7, Baden CH-5401, Switzerland e-mail:
2. Institute of Energy Systems and Fluid Engineering (IEFE), University ZHAW, Amriswilerstrasse 32a, Romanshorn 8590, Switzerland e-mail:
3. Institute of Energy Systems and Fluid Engineering (IEFE), University ZHAW, Waldeggstrasse 36, Winterthur 8405, Switzerland e-mail: