Building Airflow System Control Applications - Honeywell AUTOMATIC CONTROL SI Edition Engineering Manual

Introduction
Definitions
Airflow Control Fundamentals
ENGINEERING MANUAL OF AUTOMATIC CONTROL
Building Airflow System
Control Applications
ENGINEERING MANUAL OF AUTOMATIC CONTROL
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Need for Airflow Control ...................................................................... 266
What is Airflow Control ........................................................................ 266
Types of Airflow Systems .................................................................... 267
Variable Air Volume ......................................................................... 267
Constant Air Volume ....................................................................... 267
Variable Versus Constant Air Volume .............................................. 268
Ventilation ............................................................................................ 268
Pressurization ..................................................................................... 270
Building Pressure Balance .............................................................. 270
Containment Pressurization ............................................................ 270
Wind Pressure Effects ..................................................................... 271
Stack Effect ..................................................................................... 271
Characteristics of Fans and Fan Laws ................................................ 271
General ........................................................................................... 271
Fan Types ........................................................................................ 272
Fan Performance Terms .................................................................. 272
Fan Laws ......................................................................................... 273
Fan Power ....................................................................................... 273
Duct System Curves ....................................................................... 273
Fan Curve and System Curve Comparison .................................... 273
Characteristics of Airflow in Ducts ....................................................... 274
General ........................................................................................... 274
Pressure Changes Within a Duct .................................................... 274
Effects of Fittings ............................................................................. 276
Effects of Dampers .......................................................................... 276
Effects of Air Terminal Units ............................................................ 276
Measurement of Airflow in Ducts ......................................................... 277
General ........................................................................................... 277
Pressure Sensors ........................................................................... 277
Pitot Tube Sensors .......................................................................... 277
Total and Static Pressure Sensors .................................................. 278
Airflow Measuring Devices .............................................................. 279

BUILDING AIRFLOW SYSTEM CONTROL APPLICATIONS

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