Performance Calculation Methods for Cabinet-Type Centrifugal Smoke Exhaust Fans

Performance Calculation Methods for Cabinet-Type Centrifugal Smoke Exhaust Fans

In recent years, the market for cabinet-type centrifugal smoke exhaust fans has continued to expand, with an increasing number of products and users, making them suitable for both industrial and domestic applications. Their operating principle involves rapidly exhausting the large volumes of exhaust and flue gases generated by boiler combustion, thereby maintaining sufficient oxygen levels within the boiler to ensure normal operational efficiency. When selecting a boiler-induced draft fan, factors such as fan capacity, auxiliary airflow, and air pressure must be considered. Choose a cabinet-type centrifugal smoke exhaust fan with an appropriate flow rate, and pay attention to performance conversion, which involves changes in the impeller’s inlet conditions and outer diameter. The following provides a brief introduction to the performance conversion methods for cabinet-type centrifugal smoke exhaust fans. First, assume an average gas density (test standard) of 1.145 kg/m³, a dry-bulb temperature of 33°C, an ambient temperature of 25°C, an impeller outer diameter of 1.22 meters, and a standard impeller speed of 2900 r/min. Next, select the curve conversion coefficient used to calculate the compression ratio correction factor and specify a new model. A performance table corresponding to the impeller speed is provided. The table includes items such as the inlet volumetric flow rate, the pressure of the smoke exhaust cabinet-type centrifugal fan, the static pressure of the smoke exhaust cabinet-type centrifugal fan, and the mechanical power supplied to the impeller. At a speed of 2900 rpm, eight sets of data are recorded, applying the basic formula for performance conversion. That is, the volumetric flow rate, the static pressure of the smoke exhaust cabinet-type centrifugal fan, and the mechanical output of the propeller under steady-state flow conditions. The fan inlet upstream as specified in the contract.