This paper presents an analysis of the possibility of using recycled pork fat-based biodiesel as fuel for aviation turbo-engines. The analysis consists of the assessment of four blends of Jet A kerosene with 10%, 30%, 50%, and 100% biodiesel and pure Jet A that was used as reference in the study. The first part of the paper presents the physical-chemical properties of the blends: density, viscosity, flash point, freezing point, and calorific power. Through Fourier transform infrared spectroscopy (FTIR) analysis, a benchmark was performed on the mixtures of Jet A with 10%, 20%, 30%, 50%, and 100% biodiesel compared with Jet A. The second part of the paper presents the test results of these blends used for fuelling a Jet Cat P80 turbo engine at the Turbo Engines Laboratory of the Aerospace Engineering Faculty of Polyethnic University of Bucharest. These functional tests were performed using different operating regimes as follows: idle, cruise, intermediate, and maximum. For each regime, a testing period of around 1 min was selected and the engine parameters were monitored during the test execution. The burning efficiency was calculated for the maximum regime for all mixtures. To evaluate the functioning stability of the turbo engine using biodiesel, two accelerometers were mounted on the engine support that recorded the radial and axial vibrations. Moreover, to assess the burning stability and to identify other acoustic spectral components when biodiesel is used, two microphones were placed near the jet region. A comparative analysis between blends was made by taking the Jet A fuel as reference.

This paper analyzes the performances and the emissions of the JETCAT P80 microengine, when jet A jet A +  10% biodiesel (BD), jet A + 20% biodiesel, and jet A + 30% biodiesel are utilized as fuel, and to each of these combinations is added 5% of Aeroshell Oil 500. The performances will be assessed based on the engine speed, for the generated thrust force, the temperature in front of the turbine, and on the fuel flow. The paper will investigate the performances and the emissions generated by the four fuel blends burning when the engine is idle, at the cruise and at the max regime. This will be realized by maintaining each of these regimes for approximately a minute and a half. During the tests, the vibrations were monitored both radially and axially for the observation of the engine function regimes. From the measurements, the concentrations of SO2, NOx, and CH4 will be analyzed, highlighting the emissions of SO2. There were performed measurements to determine the fuel blend's density in order to transform the values of the fuel flow from liter per hour into kilogram per second. Having these data registered from the engine, a jet engine cycle analysis at max regime will be performed based on the combustion efficiency, the thermal efficiency of the engine, and the specific fuel consumption.

Due to the continuous run for a green environment the current article proposes a new type of solid propellant based on the fairly new synthesized oxidizer, ammonium dinitramide (ADN