Thermodynamic parameters simulation of mixed cells in gas dynamics

The techniques of closing differential equations of Lagrangian gas dynamics for multi-component medium in mixed cells are studied when a method of concentrations or similar methods are used for gasdynamic calculations. Along with a much used assumption of component compressibility equality an assumption of component pressure equality is considered in detail. In addition to these two closing techniques a new technique is proposed, derived from the assumption of component pressure increments equality. As to accuracy the latter technique turned out to be not worse than the technique, based on assumption of total pressures equality, but it is more economical and much better than one, based on the assumption of component compressibility equality. Special attention is paid to explicit difference schemes with precalculated pressure, but main results can be transferred to other difference schemes.