Performance assessment of recuperated rotorcraft powerplants: Trade-off between fuel economy and weight penalty for both tubular and primary surface recuperators

Abstract

The implementation of recuperators for gas turbine systems has been proved to be a significant technical route to meet the current challenges of reduced emissions and improved specific fuel consumption (SFC), so as to develop highly efficient, environmentally friendly aero-engines. However, they have not yet found wide acceptance in rotorcraft power plant applications, and one of the main disadvantages is the beneficial fuel saving may not offset the parasitic recuperator weight. In this paper, a computationally efficient multidisciplinary simulation framework has been implemented to systematically quantify the associated performance trade-off between the improved fuel economy arising from the adoption of recuperator and the corresponding weight penalty over a wide range of effectiveness (namely 60–75% for tubular recuperator and 80–90% for primary surface type). The performance of reference rotorcraft power plant, modeled after the Bo 105 helicopter with twin-engine configuration, has been initially assessed under a generic reference mission, and the overall approach and proposed methodology is then further extended for four representative missions. The obtained results suggest that in spite of the substantial reduction in mission fuel consumption, the deployment of recuperator may not be favorable and beneficial for certain type of missions involving short duration and/or small flight range, especially in terms of highly effective primary surface recuperator with prominent increase in weight penalty.