Kostin, R.A. Gonin, I.V. Kanareykin, A. Zaplatin, E.N. JACoW Geneva, Switzerland 978-3-95450-178-6 10.18429/JACoW-SRF2015-MOPB024 English 140-143 MOPB024 cavity simulation cathode SRF niobium Contribution to a conference proceedings 2015 2015-12 http://dx.doi.org/10.18429/JACoW-SRF2015-MOPB024 http://srf2015.vrws.de/papers/mopb024.pdf SRF cavity thermal breakdown can be analyzed analytically using thermodynamics equation. This technique is suitable for simple geometries when surface magnetic field variation can be omitted. Thermal radiation effect which is crucial for SRF gun calculations is also hard to implement properly because of complicated geometry. All of these can be overcome by using multiphysics FEA-software. This paper shows the procedure of cavity thermal breakdown calculation in coupled multiphysics analysis with dependable parameters.