Analysis of an actively-cooled coaxial cavity in a 170 GHz 2 MW gyrotron using the multi-physics computational tool MUCCA - Bertinetti, A.; Albajar, F.; Avramidis, K. A.; Cau, F.; Cismondi, F.; Gantenbein, G.; Jelonnek, J.; Kalaria, P.C.; Ruess, S.; Rzesnicki, T.; Savoldi, L.; Zanino, R. (Fusion Engineering and Design, 2019)