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Using plasma as an energy source in thermal spraying allows the processing of feedstock materials with high melting temperatures. In plasma spraying, hydrogen or nitrogen is commonly injected into the argon plasma, which increases the specific enthalpy and thermal conductivity. The objective of this study is to improve the understanding of this process through numerical simulation and to investigate the impact on the plasma properties. A comprehensive modelling approach for the electrodes in the three‐cathode plasma generator is built upon the previous work of the authors. The plasma is described as an electromagnetically reactive fluid in local thermodynamic equilibrium using temperature‐dependent thermodynamic and transport properties. The increase of flow temperature and velocity as well as the temperature distribution at the electrodes can be successfully simulated. The simulation model could accelerate parameter development for new coating systems in the future. This study completes the simulation model for multi‐arc plasma spraying using binary gas mixtures. [ABSTRACT FROM AUTHOR]

Helicopter flow computation is still a challenging task these days. The flow is instationary and transonic in a complex, time varying geometry and thus very difficult to simulate accurately. Besides that, reliable results can be achieved only if the dynamics of the blade are taken into account as well. Even in hover, but more so in forward flight the aerodynamic problem is tightly coupled to the structural response of the blades to aerodynamic forces. Rigid body motions occur as well as elastic deformations like bending and especially twist. In addition to the aerodynamic performance of a helicopter, acoustical effects become an important issue more and more. Consequently aeroacoustic data has to be generated as well as aerodynamic and aeroelastic. Realistic helicopter rotor simulations are therefore a multi disciplinary problem, where computational fluid dynamics admittedly plays the key role. [Copyright &y& Elsevier]