Open technologies for green aircraft
Modelica is a programming language that allows engineers to model complex systems. This may include design of electromagnetic systems for electric aircraft or characterisation of fluid media properties for air conditioning systems. By using this modelling language, the EU-funded project 'Modelica model library development for media, magnetic systems and wavelets' (MOMOLIB) aims to extend existing libraries for electronmagnetic components and fluid media.In particular, two new models have been developed to allow for the simulation of magnetic hysteresis. Computation of static and dynamic hysteresis should allow an accurate description of magnetic material losses when designing electromagnetic systems.A library that contains fluid properties such as dynamic viscosity and thermal conductivity of moist air and refrigerant tetrafluoroethane (R134a) has been also created. An important part of the work targeted the creation of inverse functions. Specifically, there is a function that calculates the mass fraction of water for given pressure and temperature of moist air, while another calculates the density and temperature of R134a as a function of pressure and enthalpy.A library implementing signal processing methods for analysis and reconstruction signals should improve power quality assessment. The Modelica wavelet library contains all basic wavelet transforms. This includes 15 wavelet families, discrete, inverse and continuous wavelet transform functions, as well as denoising and multi-resolution functions. Furthermore, the wavelet library supports custom visualisation of data.Since proper functionality and reliability of power electronic circuits and networks are of overriding importance in electric aircraft, the Modelica wavelet library will offer new approaches for early-stage fault detection. MOMOLIB's accurate characterisation of R134a properties will improve heating, ventilation and air conditioning systems.
Keywords
Open-source library, magnetic hysteresis, wavelet library, R134a, Modelica, fluid media
