The lowest-rank monatomic gas submodels constructed on the basis of three-dimensional symmetry subalgebras

We consider the gas dynamics equations with the state equation of the monatomic gas. The equations admits a group of transformations with a 14-dimensional Lie algebra. We consider three-dimensional subalgebras containing the projective operator from the optimal system of subalgebras. Invariant and partially invariant submodels of lowest-rank are constructed for each of subalgebras.