Assessment and Calibration of Semi-Empirical Models for Predicting Pollutant Emissions of the Erica Tiltrotor Turboshaft Engine

In this paper, the most meaningful EINOx and EICO zero-dimensional emission prediction methods from the literature are described and reviewed, while a selection of them are tuned and validated against publicly available experimental data. The equations of these models are implemented in TSHAFT, a proprietary engine simulator developed at the University of Padova which predicts the performance of turbojet engines in both design and off-design operation modes under variable ambient conditions. Then, TSHAFT is set up to predict the emissions of a generic turboshaft engine ranging in power from 1,800 shp to over 5,000 shp, and the results are compared to proprietary experimental data obtained during an aircraft landing and take-off cycle (LTO) at standard sea level conditions. Finally, the emissions of a turboshaft engine of 3000 SHP engine are calculated for two flight conditions (i.e. hover and forward flight cruise) of the ERICA tiltrotor. Finally, the paper presents the results of the comparison in terms of pollutant emissions between the engine emissions related to the baseline installation geometry, and the optimized intake/exhaust configuration.