Design and testing of a propeller for a two-seater aircraft powered by fuel cells

Abstract

This article deals with the design, manufacturing, and testing of a propeller for a general aviation aircraft fuelled by hydrogen. The feasibility of the ENFICA-FC project depended on several key-enabling technologies. In order to minimize the power required from both the batteries and the fuel cell, a highly efficient electrical propulsion system was required, in which all the components would need to yield the highest possible efficiency. The choice of the propeller for this specific aircraft was more difficult, above all because the electric motor was limited as to the torque it could handle. In addition, the propeller would also have to provide the necessary airflow for the motor, electronics, and fuel cell cooling to ensure that the temperature did not exceed the limits imposed by the manufacturer. Although a designer may be aided by modern numerical design and analysis programmes to optimize propellers, structural and manufacturing constraints can influence the final choices. Finally, the calculated performance would always have to be validated with experimental tests. An optimal propeller has been designed and manufactured to be installed on the Rapid 200 FC aeroplane. Static tests on the manufactured two-blade propeller were performed by means of a static test facility. Specific tests have also been performed to check the efficiency of the propeller when installation effects (blockage and scrubbing drag effects) are included and to verify the real efficiency of the propulsion and cooling systems, with the propeller installed in the complete converted aircraft. A good agreement between the theoretical and experimental data was obtained.

New Numerical and Measurements Flow Analyses Near Radars

“…This method has an important advantage with respect to classical methods for being able to evaluate and subsequently refuse or accept the proposed model [24,25]. This method is robust, as it provides quantitative measures of differences between the predicted and experimental data, and enables a graphical representation of these differences in the same physical units as for experimental data [26,27]. The measurement of the error d(P,O) is evaluated using Equation (1) on the entire range of the distributed data, where P(x) are the predicted values and O(X) are the observed values obtained during wind tunnel tests.…”

An Energy Efficiency Optimization Method for Fixed Pitch Propeller Electric Aircraft Propulsion Systems

“…For a given electric aircraft, three electric propulsion systems were designed under the requirements from for propellers with different peak efficiency operating points [25]. The peak efficiency operating point for propellers are the optimums operating point, the climb phase and the cruise phase respectively.…”

Flight test validation of the dynamic model of a fuel cell system for ultra-light aircraft

“…The water tank assembly consists of, a water tank, two water pumps, the filters, and a flow meter. The mass flow of the water coolant from the pump model is computed in equation (30).…”

“…In the two test cases presented here (Missions 3 and 5 of the ENFICA-FC flight test program), since code validation was the main goal of this research activity, mission GPS recorded data (Figure 9), recorded the required ambient temperature and power, and the experimental and manufacturer data of the propeller were used. 30 The electrochemical model parameters were identified from the stack voltage. This physical quantity measurement (like the electrical output stack power) was taken as a reference of the overall electrochemical performance.…”