2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/173320The flow of the relativistic imperfect fluid in two dimensions is discussed. We calculate the symmetry group of the energy-momentum tensor conservation equation in the ultrarelativistic limit. Group-invariant solutions for the incompressible fluid are obtained11 pages PS format at http://theor1.ifa.ro/~alexa/iop.psFluid DynamicsMathematical Physicstext