This technical presentation summarizes different types of fans used in mechanical engineering. It was presented by Danial Sohail, Osaid Haq, Daniyal Iqbal, and Owais Ali. The presentation describes the key types of fans like propeller, axial, forward curved blade, and backward curved blade fans. It also discusses critical parameters that affect fan performance like brake horsepower, capacity, efficiency and pressure. The optimal working conditions and proper installation of fans is emphasized. Common causes of failures in fans and blowers are also outlined.
3. Types of Fans
Fans
Propeller
Axial
Forward
Curved Blade
Backward
Curved Blade
Radial Blade
• Light or Medium Duty Application
• Ventilation Unit
• Air can be moved in either direction
• Enclosed in Cylindrical Housing
• One way direction of air
• Used in Clean environment
• Moderate Efficiency
• Moderate Noise Level
• Used in Clean environment
• Highest Efficiency
• Lowest Noise Level
• High Temperature
• Any Environment
• Lowest Efficiency
• Highest Noise Level
5. Design Speed 10 – 15% less than critical speed of fan
Maintenance of speed and mass of rotating element
Lack of maintenance can lead to serious damage/failure
Stable Inlet Conditions
Ducts should be designed to ensure:
Adequate volume of clean air or gas
Stable inlet pressure
Laminar flow
Controlled moisture, dirt content, barometric pressure, density
Optimum Working Conditions
6. Rigid stable foundation.
Bearing supported structure
Leak proof, airtight minimum friction loss duct work
Flow control devices for inlets and outlets.
Installation of Fans
7. Delivers quantity of air or gas at a desired pressure
Moderate to high pressure devices.
Compression by helical lobes or screws.
Blowers
8. Process Instability
Start/Stop Operation
Demand Variation
Mechanical Failures
Causes of Failures in Blowers
9. Fluidizers are devices to provide moderate to high pressure transfer of
non-abrasive, dry materials
Fluidizers
10. Air Leakage
Couplings Misaligned
Dirt in Air
Wrong Direction of Rotation
Insufficient Air Suction
Causes of Failures in Fluidizers