A system is provided. The system comprises a computer system comprising at least one processor, a thermodynamic state solver application, and a thermodynamic system solver application. When executed by the at least one processor, the thermodynamic state solver application computes a flash equilibrium state solution for each of a plurality of nodes in a thermodynamic network and determines for each of the plurality of nodes at least one sensitivity of a first thermodynamic property with reference to at least one second thermodynamic property. When executed by the at least one processor, the thermodynamic system solver computes a pressure at each of the nodes and flows between the nodes based at least in part on the sensitivities, wherein a result based on the pressures and flows is determined.