Cross-ventilation mechanism with large openings is different from one with small openings. The kinetic energy occurred at the windward opening interfere with the airflow characteristic of the leeward opening. The effect depends on opening conditions. In this paper the correlation between airflow characteristics and the opening area ratio and relative locations is studied through wind tunnel experiment and CFD. It is concluded that the airflow characteristics could be divided to three cases by the ratio of opening area (A_L/A_W) and the airflow angle to windward opening (β). In the case of A_L/A_W ≪ 1, the airflow is dominated by static pressure. In the case of A_L/A_W > 1 and β≒0, the airflow characteristics is defined by only windward opening shape. In the other cases, the airflow is influenced by both of kinetic energy and static pressure.
