A three-dimensional unstructured code (CRUNCH) for generalized real gas mixtures with a two-equation turbulence model is described. The unstructured framework is an edgebased algorithm that allows for multi-element (tetrahedral, prisms, hexahedral) grids. Formulation of viscous flux terms for hybrid grids within this framework is presented. The influence of flux limiters on the evolution of turbulent scalars (using a two-equation k/e framework) and species equations is analyzed indepth. In particular, the sensitivity of viscous solutions on tetrahedral grids to the accuracy of the inviscid flux is highlighted. For efficient solutions of large three-dimensional problems, a parallel domain-decomposition strategy with an implicit solution procedure has been implemented. A number of three-dimensional test cases for turbulent/reacting flows are presented and the code is shown to provide good results within the confines of the turbulence model/chemical reaction mechanisms used.