Effect of inclination angles on the heat transfer and pressure drop characteristics of brazed aluminium heat exchangers under dehumidifying conditions.

The study presents the effect of inclination angles on the air-side heat transfer and pressure drop characteristics for multi-louvered fin and flat tube heat exchangers under dry and wet conditions. For six heat exchangers with different louvre geometries, a series of tests were conducted for the air-side Reynolds numbers of 100-600. The inclination angles from the vertical position were 0°C, plus or minus 15°C, plus or minus 30°C clockwise. The pressure drop increased systematically with the inclination angle, but the heat transfer rate did not influenced significantly by the inclination angle. The louver angle and fin pitch had a moderate effect on the heat transfer rate, and friction factors increased significantly with the louvre angle and fin pitch.