H. Clay Moore & Associates Key Account Manager - Nuclear Fan & Systems Chris Carr PE H. Clay Moore & Associates Rod Furniss Howden North America Key Account Manager - Nuclear

3 Aerodynamics • Pressure & Flow Definitions and Measurement • Development of Fan Curves • Performance of Various Blade Shapes • Fan Controls System Effects

HNA Profile

Aerodynamics What is a Fan? Any device for producing a current of air by the movement of a broad surface or a number of such surfaces. 4

Aerodynamics Fan Flow Rate Often called inlet volume Pressure & Flow Definitions and Measurement Fan Flow Rate Often called inlet volume Measured at the fan inlet, by convention Measured in cubic feet per minute (cfm) May be converted to scfm (standard cubic feet per minute), or mass flow (lb/hr) Fan manufacturers commonly use acfm (actual cubic feet per minute) 5

Aerodynamics Pressure Absolute Pressure Barometric Pressure Pressure & Flow Definitions and Measurement Pressure Force per Unit Area Commonly measured in psi or inwg Absolute Pressure Pressure when the datum is absolute zero iiAlways positive Barometric Pressure Absolute pressure exerted by the atmosphere Always positive Gauge Pressure Pressure when the datum is barometric pressure May be positive or negative 6

Aerodynamics Static Pressure Velocity Pressure Total Pressure Pressure & Flow Definitions and Measurement Static Pressure Pressure due to degree of compression and density only May be positive or negative Velocity Pressure Pressure due to rate of motion and density only Always positive Total Pressure Algebraic sum of static and velocity pressures at a point 7

Aerodynamics Fan Total Pressure Fan Velocity Pressure Pressure & Flow Definitions and Measurement Fan Total Pressure Difference in Total Pressure between the fan outlet and fan inlet FTP = TPo - TPi Fan Velocity Pressure Pressure corresponding to the average velocity at the fan outlet FVP = VPo Fan Static Pressure Fan Total Pressure minus Fan Velocity Pressure FSP = SPo – TPi Static Pressure Rise Difference in Static Pressure between the fan outlet and fan inlet SPR = SPo - SPi 8

Aerodynamics Image area Fan Pressure Terms Pressure & Flow Definitions and Measurement Fan Pressure Terms For a Given Fan, SPR is iiiAlways Greater Than FSP If the Specified Pressure is iiiAssumed to Be FSP, the Fan iiiSelected Will Be Smaller Image area 9

Aerodynamics Image area Pitot – Static Tube Pressure & Flow Definitions and Measurement Pitot – Static Tube Image area 10

Aerodynamics Image area Fan Laboratory Test Setup Pressure & Flow Definitions and Measurement Fan Laboratory Test Setup Image area 11

Aerodynamics Development of Fan Curves Fan Curve Image area 12

Aerodynamics Development of Fan Curves System Curve Image area 13

Aerodynamics Image area P-V and Peak Fan Pressure Development of Fan Curves P-V and Peak Fan Pressure Image area 14

Aerodynamics Development of Fan Curves Selection Range Image area 15

Aerodynamics Common Blade Shapes Airfoil Performance of Various Blade Shapes Common Blade Shapes Airfoil Backward Curved / Backward Inclined Radial / Radial Tip Forward Curved Axial 16

Aerodynamics Image area Airfoil Highest Efficiency Centrifugal DDesign Performance of Various Blade Shapes Airfoil Highest Efficiency Centrifugal DDesign Limit Load HP Characteristic Low Noise Usually for Clean Applications Largest Diameter Centrifugal Highest Cost Centrifugal Image area 17

Aerodynamics Image area Backward Curved / Backward Inclined Performance of Various Blade Shapes Backward Curved / Backward Inclined Essentially a Single TThickness Airfoil Efficiency slightly less than AAirfoil Limit Load HP Characteristic Low Noise For Clean or Dirty AApplications Lower Cost than Airfoil Image area 18

Aerodynamics Image area Radial / Radial Tip Lower Efficiency Performance of Various Blade Shapes Radial / Radial Tip Lower Efficiency Continuously Rising HP .. CCharacteristic Higher Noise Levels May have Predominant BFP TTone Smaller Diameter Easily Armored for Erosive SService Lower Cost Image area 19

Aerodynamics Image area Forward Curved (SiroccoTM) Lower Efficiency Performance of Various Blade Shapes Forward Curved (SiroccoTM) Lower Efficiency Continuously Rising HP CCharacteristic Smallest Diameter Centrifugal Suited for High Volume/Low PPressure Distinctive Dip in P-V Curve Seldom Used Today Image area 20

Aerodynamics Image area Axial Airflow Parallel to Axis of RRotation Performance of Various Blade Shapes Axial Airflow Parallel to Axis of RRotation High Efficiency Limit Load HP Characteristic Low Noise Suited for High Volume/Low PPressure Adjustable or Controllable Pitch Distinctive Dip in P-V Curve Controllable Pitch has Higher CCost Image area 21

Aerodynamics Fan Control Reasons for Providing Fan Control Fan Controls Fan Control Reasons for Providing Fan Control Methods of Control Efficiency Comparison Mechanical Arrangements Control Criteria 22

Aerodynamics Reasons for Providing Fan Control Fan Controls Reasons for Providing Fan Control Uncertainty in System Calculations Safety Factor or Margin Expected Changes in the System with Time Normal Process Variations Provisions for Extraordinary Events 23

Aerodynamics Image area System Pressure Loss and Fan Design Pressure Fan Controls System Pressure Loss and Fan Design Pressure Image area 24

Aerodynamics Fan Controls Moving the Operating Point Image area 25

Aerodynamics Fan Controls System Duty Cycle Image area 26

Aerodynamics Methods of Control None Outlet / System Damper Fan Controls Methods of Control None Outlet / System Damper Inlet Box Dampers Variable Inlet Vanes (VIV) Variable Speed Blade Pitch Control Combinations of the Above 27

Aerodynamics Fan Controls Outlet Damper / System Damper Image area 28

Aerodynamics Discharge Damper

Aerodynamics Fan Controls Inlet Box Dampers Image area 30

Aerodynamics Fan Controls Inlet Box Dampers Image area 31

Aerodynamics Fan Controls Inlet Box Dampers Image area 32

IBD Discharge

IBD Discharge

Aerodynamics Fan Controls Variable Inlet Vanes Image area 36

Aerodynamics Image area Physical Arrangement of Cantilevered VIV Fan Controls Physical Arrangement of Cantilevered VIV Image area 37

Aerodynamics Image area Physical Arrangement of Radial Vane Control Fan Controls Physical Arrangement of Radial Vane Control Image area 38

Aerodynamics Fan Controls VIV Fabrication Image area 39

Aerodynamics Fan Controls Variable Inlet Vanes Image area 40

Aerodynamics Fan Controls Variable Speed Image area 41

Aerodynamics Variable Speed- VFD and Gỳrol Fluid Drive Rotating Stall Fan Controls Variable Speed- VFD and Gỳrol Fluid Drive Rotating Stall

Aerodynamics Fan Controls Blade Pitch Control Image area 43

Aerodynamics Fan Controls Efficiency Comparison Image area 44

Aerodynamics Image area Fan Controls Physical Arrangement of Various Control Devices Image area 45

Aerodynamics Image area Fan Controls Physical Arrangement of Axial Blade Pitch Control Image area 46

Aerodynamics Control Criteria Turndown / Leakage Fan Controls Control Criteria Turndown / Leakage Sensitivity to Change / Stability / Transients Accuracy Required Repeatability Expected Efficiency Acoustic Considerations Structural Considerations 47

System Effects – Poor Flow 48

System Effects – Poor Flow 49

System Effects – Poor Flow 50

System Effects – Poor Flow 51

H. Clay Moore & Associates Key Account Manager - Nuclear Fan & Systems Chris Carr PE H. Clay Moore & Associates Rod Furniss Howden North America Key Account Manager - Nuclear