Study of an Axial Micro-Turbine with 1D Model Including Various Fluids or Zeotropic Mixtures and Validated against Experimental Results

A 1D multi-fluid performance prediction model has been developed using an original approach that combines various methods from the literature. It has been compared with a great number of experimental results from tests involving five different fluids or mixtures and has demonstrated a strong ability to accurately predict turbine internal efficiency (±\pm5 efficiency points and ±\pm15% internal power), regardless of the fluid. This accuracy is particularly notable since most of the tested points are in severe off-design conditions. Moreover, the higher the efficiency, the better the accuracy, suggesting a very good capability of the model in more conventional operating conditions. Therefore, further experimental work is needed at better operating points to complete this validation. Additionally, the comparison between numerical and experimental mass flowrates has highlighted the necessity of considering the pressure ratio across the turbine when determining nozzle efficiency. Finally, the partial admission model composed in this study seems to be relevant but require more investigation at better operating range and with other partial admission.

Further work is under study with a second turbine(  5kWe). Also a two-phase behavior in the turbine’s injector is being implemented into the model.

Work In Progress