Advances in aerodynamics of power turbines for marine and aviation applications

The use of power turbines has the advantage of flexible output load adjustment, and is a major configuration of marine gas turbines and aviation turboshaft/turboprop engines. Marine gas turbines and aviation turboshafts and turboprop engines generally have multiple working states and multiple working conditions change laws, which cause the aerodynamic performance of power turbines to fluctuate greatly with changes in working conditions, and different variable working conditions have a severe impact on the turbine loss characteristics. Therefore, it is necessary to deeply understand the internal flow mechanism of power turbines under off-design working conditions in different power turbine application modes, and carry out researches on the design methods of power turbines under wide working conditions. This paper summarizes and analyzes the recent advances in the field of aerodynamics of power turbines for marine and aviation applications. This review covers the following topics that are important for power turbine designs: (1) turbine flow loss prediction models under multiple operating conditions, (2) aerodynamic design and flow mechanism of power turbines for marine gas turbines, (3) aerodynamics of variable speed power turbines for turboshaft/turboprop engines, and (4) other issues about power turbines for marine and turboshaft/turboprop engines. The emphasis is placed on the aerodynamic design and flow mechanism of marine and aviation power turbines. We also present our own insights regarding the current research trends and the prospects for future developments.