The Computational Fluid Dynamics (CFD) code that has been used extensively for combustion applications within GE is CONCERT. CONCERT is a fully elliptic body-fitted CFD code based on pressure correction techniques that solves the three-dimensional (3-D) flow in an aircraft engine combustor. The geometry representation is given by single block structured grids. This paper gives an overview and presents some early applications of the Advanced Combustion Code (ACC) which is currently being developed to further advance the use of Computational Combustion Dynamics (CCD) at GE. ACC will have complex geometry representation capability via unstructured multiblock grids, and will comprise of a number of advanced combustion/spray/turbulence models that are being developed in a modularized fashion. The ACC solver is based on a fully implicit pressure correction algorithm with colocated grids. The development of ACC is taking place by comparing, as far as possible, the results against corresponding CONCERT calculations. Results of a systematic evaluation of various combustion models within the framework of a non-swirling jet diffusion flame using ACC will be presented. Full 3-D combustion calculations have been performed in the dome of single and multiple annular combustors: the corresponding flow and temperature fields and emissions predictions will be presented.Copyright © 1998 by ASME