The application of the new method for mathematical modelling of abnormal operation of the onboard systems of the spacecraft

The article is devoted to software design of lumped-element simulation models of the spacecraft subsystems. Considered type of engineering systems could be complicated due to 1) non-linear relations impact, 2) bi-directional bonds and 3) distributed structure, including huge element count and complex bonds network. In the previous publications we suggested a new approach for simulation models design to address the items above. Based on the new approach we implemented software package to create simulation models of engineering systems. Unlike known analogues, the package equipped with non-linear solver is capable to model non- linear physics. With this package a model could be constructed just via combining of available physical domains, no additional source code required. Spacecraft thermal control subsystem was modelled with the package. In this article we modified previously developed model of thermal control subsystem to simulate several failures, including the leakage of the hydraulic circuit. This requires to update the models of elements of the subsystem to become adequate at a low liquid pressure. We model the subsystem evolution taking into account considered failures under different external conditions and got expected results.