NUMERICAL INVESTIGATION OF VENTILATION METHODS FOR NiCd BATTERIES OF AN INDOOR SUBSTATION

Abstract

Performance of ventilation inside NiCd battery room was investigated numerically utilizing Ansys Fluent 19.0. The model was built and mesh by ANSYS design modeler yielding around 3.4 million elements after making good use of symmetry B.C. Validation was done against experimental published data and comparison between various turbulence models was performed. A parametric study is done to explore the impact of three various factors on the efficiency of the ventilation system. First, the relation between (ACH) utilized and the average hydrogen concentration. Second, the impact of changing inlets and outlet grilles location under fixed 20 (ACH) on hydrogen concentration. Third, the impact of storing batteries in double vertical racks on the ventilation performance, which offered the best ventilation performance utilizing wall type inlet grille at the lower wall section and outlet grille at the roof, while the batteries racks are surrounded by curtains to act as spot ventilation which offered the opportunity for choosing lower value of ACH (10) in order to reduce the equipment and energy cost which maintained an acceptable value of hydrogen concentration 0.66%.