Condensers for separation of CO(2) and steam are central devices in oxygen-fired power plants for CO(2) capture. This work is the first part of a project aiming to optimize the design of a H(2)O/CO(2) Oxy-Fuel condenser. The project aims to achieve an in-depth understanding of the separation process at varying thermal conditions and with varying fluid compositions. COMSOL simulation tool has been used to study fluid flow, heat transfer and condensation process for H(2)O/CO(2) mixtures. The simulated condenser is a tank with all of its accessories. Boundary and initial conditions are set based on earlier works. H(2)O and CO(2) are considered as the main components for flue gas. The results show that with the proposed design, the condenser will be able to condense about 75% of water content in flue gas stream. The resulting flue gas stream after the condenser contains more than 97% CO(2). The information gained through the proposed project are important design data for improved condenser solutions that need to be implemented in order to reduce capital cost and increase the thermal efficiency of the power plants.