A molten carbonate fuel-cell stack is a new, non-standard component in power-generation systems. Its power-generation capability and the safety operation with regard to load-following conditions must be identified. A three-dimensional dynamic stack model using computational fluid dynamics technique is developed. The stack model developed includes the macro-processes of gas transport, chemical reaction and heat transfer at cell level and the heat and gas transport at stack level. It also incorporated the micro-processes of power and heat generation due to electrochemical reactions at electrodes. The model equations and the program implementation have been presented here.