Although the specialty of COCHEM Flow is in modelling wet steam flow with homogeneous and heterogeneous condensation, the program can be also used for any other general calculations of two-dimensional compressible flow, including a transonic flow with shock waves. Thanks to the flexibility and robustness of the integrated FE-mesh generator, COCHEM Flow simulations can be done in any two-dimensional domain of arbitrary shape, including turbine planar blade cascades. When using the single-phase model, the program calculates basic properties of the flow field, such as velocity, density, pressure, Mach number, etc. All these quantities can be graphically displayed or exported for further post-processing. The mathematical model is based on the system of Euler equations, which is extended by additional equations for nucleation and transport of the liquid phase. The model, however, does not consider viscosity, nor turbulence.
When the two-phase model is used, COCHEM Flow can determine zones of homogeneous condensation, the number of originating droplets, their average size and the corresponding wetness. It also can calculate steam sub-cooling and find the position of the so-called Wilson line and the condensation shock. In addition to homogenous condensation, the code can also simulate heterogeneous condensation, caused mainly by chemical impurities dissolved in the steam or the binary-condensation model can be used. It is possible to determine the solubility of corrosive salt (NaCl) in the superheated steam and to assess its precipitation. The code determines the position of "Salt solution zones" and calculates the concentration of sodium chloride in the created droplets. COCHEM Flow determines steam parameters on the blade surface and allows thus the prediction of corrosion attack on the blades.